According to This thread, Birrman54 is going to test the Spir@l, Maze-2, Innovatek rev3, Innovatek Flatflow, Gemini High flow, and TC-4 in his first installment. He is going to test using both an Eheim 1250 and 1048 (not sure which radiator or tube size he is going to use).

The results will be posted at www.subzerotech.com.

Here is the list of most of the blocks he will be testing (there are others he is going to add once he gets ahold of them)...

1. Spir@l (www.dtekcustoms.com
2. Maze 2 (www.dangerden.com)
3. Maze 3 (www.dangerden.com)
4. Swiftech MCW462-U (www.cooltechnica.com)
5. InnovaCool Rev 3 (www.highspeedpc.com)
6. InnovaFlat (www.highspeedpc.com)
7. Space 2000SE (www.case-mod.com)
8. TC-4 (www.dtekcustoms.com)
9. ?? (Steve from www.ocforums.com chancell@ihug.co.nz)
10. ?? (Steve from www.ocforums.com chancell@ihug.co.nz)
11. Gemini Hi-Flow (www.geminicooling.com

From the few tests I have read (one at Overclockers , the other at PCReports (Need to use a translater on this one, its in German), the best blocks all had 10mm OD (3/8 OD) tubing, with only the Eheim 1046 or 1048 pumps. Oh, and the blocks had large amounts of surface area (unlike the Maze-3).

It makes sense that the best performing blocks with smaller pumps would have smaller fittings. This increases water velocity as it goes into the block and improves heat transfer from lowering the size of the boundary layer. That doesnt mean that these blocks are universally best, however, as other blocks may be designed for bigger pumps and more pressure.

That was exactly my point with Birrman. I see no mention of temperature measuring, number of replicates, testing parameters.

I have a few blocks here I will be testing too:

Center Inlet "maze type"
Maze2
Spir@l
sysfx dual channel

Die Area Impingement
Swiftech MCW462U
Swiftech MCW462UH

Others
Innovatek rev3
Heatkiller 1.5

That really doesn't say much about the quality of the final results though does it?

Yea science and proper analysis procedures break down ALL the time. Perhaps we REALLY need to be asking our ministers which blocks to use?

Your example is actually consistent with my statements as well. Inproper testing methods don't always yield useful results. Please find me an example of where thermodynamics breaks down. An example (from the life sciences) that would be more consistent with what I am talking about would be the observation that pharmaceutical development times and efficiency have been dramatically reduced since the 80s when biochemistry really became a popular science. Chemists and biologists began to elucidate enzymatic pathways and fundamentally understood how they work and where they are going wrong in sick people. This let them target particular pathways with drug therapy, and greatly accelerate the whole R&D process. The same thing is needed here. You will never understand heat transfer and fluid movement and the important design variables with your approach. Without that understanding the improvement of overall systems will be slow and fraught with misinformation (lets just inject this into rats and see what happens?).

A few weeks of thought in designing an experiment can save you a few months of testing; figure out what your questions really are and then focus your studies on getting to that. To me, the goal would be to educate readers in heat transfer and to provide test results that are useful in mixing and matching a good performing complete setup or in building a good custom block. You can't get there (easily) by testing just a whole bunch of complete kits; there are too many variables. Consider the variable pressure production of different pumps of approximately the same GPH rating. This will influence the performance of the setup and in particular the need to move to larger fittings to try and lower the resistance and get higher flow to a block. If you have pressure drop information on the blocks as well as temp, then you can try to match a block to the pump you are using. Many people (myself included) like to cool in smaller cases and so pump choices are limited. Case size also limits radiator choice somewhat and that will also affect block choice. I choose fans based upon manufacturer supplied curves all the time without needing to put them in my case first to "test" them. I don't understand why water cooling equipment is any different, other than the fact that the manufacturers don't (can't? won't?) provide that data so testers need to generate it themselves.

I can see that my comments have kept a few people up late...

Powerhouse, I think you've got a couple of misconceptions.
(so I'll list what I see, and you tell me if I'm wrong!)
1-Although water temperature is a factor in the performance of a waterblock, controlling that temperature is not something that is a part of a common water cooling setup (i.e. there is no chiller/heater). As a result, water temperature is irrelevant, for the purpose of testing a waterblock. If you don't agree, then look at it this way: if a block's performance was (theoretically) optimal with a coolant temp of 15C, what could you really do with that information?

Also, in your reply to pHaestus, you (essentially) stated that temperature should be tested as a function of flow rate, when really, it's the other way around. Water temp is not relevant, it's just a consequence.

In the same reply, I don't think you quite understood that the test of a WB would be performed at different flow rate with a fixed (read controlled) water temp (wether or not there is a rad is irrelevant), for the purpose of finding its optimal cooling setup. Selecting a rad is a separate issue, which makes my case for matching components.

Your frying pan analogy is funny, but doesn't quite match the number of factors involved in water-cooling. But just for fun: what if your frying pan had a thickness of 10mm? What if it was cast iron, instead of Aluminium? What if the stove was turned on 7 instead of HIGH? What if you matched a heatsink with a fan providing it with its optimal air flow rate? I think it would be of interest...

2-The heat dissipation properties of a waterblock do NOT change with the temperature of the coolant. The only situation where this statement would not be true, is if the temperatures would change the physical state/properties of the materials involved (i.e. tygon melting at 80C, water boiling at 100C, copper turning into liquid at 2500C, etc... I know that it's hard to believe.

Now I'll answer some questions/post comments...

PH: you suggested "comparing the difference with the new CPU and adjust all you numbers accordingly". Now you're talking about a lot of expensive gear!!! Keep in mind that this gear CANNOT change from one test to the other, so if something fails, it would have to be replaced with EXACTLY the same components, which may or may not be available anymore. Also, some gear fit for an old Duron, may not even be appropriate for an Athlon Xp, and vice versa.

PH: about load testing low/medium/high
Unnecessary, and too time consuming. it would be far simpler and more accurate to measure the performance of each component individually under ONE typical environment.

About reviews/tests: if all you're going to do is ignore the numbers (which is fine) and take several people's opinions on which is best, then that'll work well, for air cooling. For water cooling, there are several components available together or seperately, but the best of each will not yield the best results.

About the time it takes to do the tests:
I would trust a test if the testing methods were consistant, and gave me usefull numbers, REGARDLESS of how long it took. The method/results speak for themselves. How long it took to get those results is IRRELEVANT.

About pumps:
This is one point that you do have, in that tests don't match real life. e.g. if an optimal flow rate has been established at Xgpm for a particular configuration, there may or may not be a pump available to reproduce the exact flow rate. Pumps do perform differently based on the flow resistance of a rig, but this can be equated with the "head" rating of the pump, and so, you already have all the data you need. (actually you'd still need the net flow resistance of a particular setup, see below)

About rads:
as the OC review suggested, there may be a "sweet spot" to most rads. Wouldn't it be nice to know what they are for each rad? Or at least how to find it?

About different rigs:
My point is that you may be able to reach the same results, with a completely different rig.

About results:
There are a number of conditions that would affect an actual rig, and those include: tubing length (not size), actual volume of coolant, coolant additives, number of elbows, ambiant temperature AND humidity, placement of radiator, effective rad fan flow rate, etc... but those are simply beyond anyone's control. Knowing that though, basic recommendations can be made, but otherwise, all those factors add up to establish THE ACCEPTABLE MARGIN OF ERROR of any test. Sure 0.1C temp testing accuracy would be nice, but is it necessary?

About the Maze-3:
It may not be a significant factor, but the interior is sandblasted, giving it a higher surface area.

pHaestus:
Your testing rig sounds very nice. The importance will be with your testing methods, as they have to remain consistant. It may be atypical, but a typical person would not get a flowmeter, pressure gauge, and many temp sensors, they'd just use the same gear, but straight out.

pHaestus: I like your graph... It'd be nice to see the data on a wider range though (take those results, determine a range that is of interest, then exceed it at both ends by 25%). so 3 GPM (180 GPH) would be pretty good for a MCW 462U, huh?

myv65:
You've nailed it right on the head. There is a temperature point where the wb will not cool under, regardless of flow rate. What I'm wondering is, if there's a sweet spot for rads, could there be one for WB?

About this discussion: there is one very important factor that has barely shown up:
MONEY!!!
In any company, when a project comes up, there is a cost study made, for the "best bang for the buck". Here, the consumer is the company...
My point is this: you could spend an outrageous amount of money on a water cooling rig, but you may never be able to sell it, simply because it's not cost efficient.

Would anyone really buy a solid silver block, with 3/4 inch barbs?

Wow I saw the references to PH in that post and was quite confused: I don't agree with that? Did I say that? Then I realized PH = Powerhouse not pHaestus. I think that you and I are basically in agreement that you should try to learn something useful from the testing or else it doesn't have very much point.

For many pieces of information, 0.1C accuracy really is needed. The error propagation otherwise gets really out of hand. You see differences, but if they fall within the overall error they aren't necessarily real. With a water temp and CPU temp probe that are both +/-3C, you need some BIG differences to spot. That isn't even accounting for the compression of most people's CPU temperature due to how they measure it.

The MCW462U data is Bill's not mine. I purchased a much larger (industrial) pump to counteract the restriction of the flowmeter and allow me to generate flow curves at much higher GPM. The curve I have there is the most the Eheim 1250 could accomplish :)

The issue becomes the amount of heat the pump throws into the water when throttled back, and properly accounting for that (with good water inlet temperature measurements). That is why I want to move to a controlled water bath instead of a radiator.

The issue for testing is also very much one of money. Especially the accurate temp monitoring and the production of a good die simulator. Look to spend LOTS for accurate results, and then contend with the problem that the average end user just wanted you to give them a "clear winner" and a lot of pictures of the blocks and really isn't interested in the real information that is in the tests.

Here Here!!! 100% agree on the cost issue!

If you ask me, DangerDen should be performing these tests, so should resellers. It certainly would be in their interest.

Of course we'd still need impartial testers... like you pHaestus (sorry about the PH thing)!

About the temp probes, and accuracy:
My point was that since the rigs out there are all going to be slightly different, and if the variation in those results range in the +/- 3 degrees (as an example), given the exact same equipment, then the temp probes you're using right now would do just fine. We just don't have those numbers. What we have, is most people reporting their results within a +/- 1C, with few reporting at +/- 0.1C, so definitely, you would need at least +/- 1C accuracy.

The next step would be for you to go through the exercise of determining the sources of error in the testing conditions, and equating them in terms of a percentage. If for example, you found that a change in humidity from 20% to 80% (95% plus is common here in Houston, Texas) affects results by .3 degrees, then that's the accuracy of the test: 0.3 degrees. So you get a temp probe that measures +/- .1 degrees, and state your results with that accuracy. If ambiant temp also affect results, then the margin of error is ADDED to the previous one.

CPU compression is another one of those "beyond my control" variables. I think that the best thing to do is to just describe what the WB comes with, and specifically describe how you set it up (i.e. spring screws turned way down, then turned back 1/2 turn).

You've mentionned the pump induced heat many times, but I've been ignoring you! It's a good case for controlled environment testing, like you said.

Yes, the user wants to know what's best, but what's best for one, may not be best for another. If there's one thing that I found to be consistant, is that everyone is different! We have people in this forum from all over Europe, and they certainly don't have access to the same supplies that we do.

I do appreciate a lot of what you guys are saying, I just don't think the majority of people out there will really care if the temp is 0.1C off or not in your tests. Let alone care about the effects of Humidity (I dont even know what the humidity is in my area, and I would imagine that most other people don't either). The fact that you break this down to the nitty gritty detail, is great (whatever floats your boat I suppose). However, if after you completed your testing, and someone else did a test and was say only 1-2C off in there temp compared to yours (but their methods were more in line with what I proposed) do you think the majority of comsumers would really care?

To answer some of your questions bigben2k:

1. Will these tests be expensive? Perhaps, but I would imagine that someone from one of the major OC/Performance/Cooling websites (Birrman54, pHaestus, etc) will be able to get the equipment (WB's, Rad's, Pump's, etc) for free (just like people get Motherboards, Ram, CPU's, etc) for testing purposes (probably have to return them afterward though:cry: )

2. People will always have different gear (that's the name of the game with PC's), but if you had a baseline test system, you could just swap in a different CPU (and new Motherboard if needed) and show the difference with the newer CPU. So if you started with an AthlonXP, you could swap that out for a T-Bred, test it with your base system. This would give people a good comparison of what to expect with this new CPU. About the only time this wouldn't work out as well, is if you went from say an Athlon to a P4 Northwood (then you would have a different WB to test as well as the different CPU).

3. Most testing I have seen done has included a CPU under Idle and Load condititions.

4. I don't ignore the numbers in the tests I've read about online. My point was, that you don't need to read the numbers on 15 different sites, to see that one particular Heatsink is the best (in a varity of setups and systems). Your second comment is what I have been trying to get across. "...the best of each will not yield the best results" pHaetus is only testing WB's, so his test might show a WB performing better than all the rest, but when you put it in a system (realword not some lab), the same WB might suck.

5. I agree about the Rads, and I would even suggest that larger Rads perform better on highflow blocks, while smaller Rads perform better on lowflow blocks (course haven't seen any test on this yet).

6. Different rigs might change the numbers a bit, but you are correct, you could get the same results with some completely different Rig.

7. My points on tubing size have to do with the fact that you see numerous posts about people having 5/8 OD tubing (vs. say 3/8 OD tubing) and this gave them 1-3C better performance. Again, this would help people decide if they really needed the big 5/8 tube or could they use the smaller 3/8 tube and still have acceptable performance. I myself perfer the 3/8 OD tubing as it takes up less space, and is easier to work with (bendable, easier to poke it in out of the way places, etc). I agree with the 0.1C temp testing, it really isn't necessary for the Majority of people.

I think we're starting to see along the same lines... or at least understand our differences! Thanks for your patience PowerHouse, it's really nice to have this civilized conversation.

Lab vs realworld:
I think that the biggest objection to using a PC for testing, is that the cooling rig changes from tester to tester (i.e. different rad, different pump, etc). Most reviews of WB I've seen are individual reviews, not waterblock roundups.

In waterblock roundups (and I've only seen maybe 3), the test rig is of course the same. The problem is, the rig may not be optimal for each waterblock (which I think is your complaint, perfectly valid).

The other problem, and by far the biggest one, is that new products keep coming out. Now, I don't know about you, but I'd rather test a new individual component, under controlled conditions, find out its optimal running conditions, and see how it could be matched up with the other items I would have already tested, instead of running the whole set of combinations all over again.

to answer a few of your points...

1-If the equipment has to be returned, then it's not possible to test again under the same conditions.

2-Again, a very extensive set of combinations to test.

3-Agreed, but they don't give me much usefull information, not even a Best OF", in some cases.

4-Of course you ignore the numbers. You ignore them because you know that there is no way that your results will be exactly the same. You use the numbers to see who came out on top, but that's the extent of it.

5-Yes, high flow blocks do better with large rads, but no, low-flow blocks do NOT perform better with small rads, actually, they are more likely to perform better with a large rad too!

The lab, has to be setup in a way to simulate a PC. The point is not that a lab is different than a PC (yet it is). If it's any easier, think of the lab as another PC, that will give exactly the same results, no matter how often you run the same test.

More importantly, the lab gives one the ability to test individual components, again, with consistant results.

The purpose of testing individual components, is to give you the ability to match different components, and get optimal results.

Here's an example: The hottest radiator right now is the Black Ice Extreme (BIX) yet if people knew that a $20 heater core, picked up at any auto parts store will perform just as well, if not better than the BIX, then people would stop wasting $50+ on it, unless they just wanted something that looks pretty, and is made to fit very nicely in their case (my personal opinion).

6- (agreed)

7-Tubing size has a number of effects, under a number of different circumstances.
a)a larger tube will increase the water mass of the system, thereby increasing the thermal capacity (very often ignored)
b)a larger tube will REDUCE the flow resistance, but bear in mind that unless the internal pressure has been reduced to under about 5 psi, there will be no noticeable increase in flow. This can be measured as a function of flow rate (i.e. water travels at a smaller speed in a larger tube, given the same flow rate)
c) tubing size should be at least as big as the smallest opening of any of the components. (i.e. if you use 3/8 where all your components are 1/2, then the tubing MAY become a significant factor in flow rate.
d)The biggest flow restrictor, is by far the waterblock. It includes at least 2 90 degree bends, as water comes in and out of it, (an additional 90 degree if you use 90deg fittings right on the waterblock) and usually has at least 6 90 deg bends inside. Also, sometimes the water channels are not straight, are not smooth, have intrusions that cause turbulence, etc... all of which are good for cooling, but bad for flow.

A smaller tube (i.e. 3/8) is physically smaller, and does occupy less space, but I don't believe that in most setups, using a slightly larger hose is actually an inconvenience.

A m8 of mine pointed me in the direction of this article http://www.amdmb.com/article-display.php?ArticleID=179
Which looks into this exact issue. His conclusions get back to the old issue about ballancing the componants and properties are of greater value than simply increasing waterflow with bigger tubing or pumps.

not all blocks have that many 90 degree bends. the spir@l has none (within the block) for example. the Maxe2 doesnt have any (all the bends looks greater than 90 degrees, except for 2 that look close...).

anyhow........damn it took me forever to read this thread!

also, ive been wondering why no-1 has made a high-flow block with lots of surface area. theroretically, a block with higher surface area should transfer heat to the water a lot better. for example, make a block with the inlet on one end, and an outlet on the opposite end. .have like a diamond-shaped island in the middle. have a bunch of vertical fins on the sides of that diamond. id draw up something, but i dont have any imaging software (MSpaint wont work becuase it doesnt save in .jpg format).

CD, you're right on many points, but there are blocks of that design being made, by individuals!

A spiral may not have 90deg bends, but it does have a resistance to flow. I referred to 90 degree bends because they're an easy way to calculate flow restriction. Spirals are a whole different ballgame...

Some of the most ingenious designs call for posts coming up from the center of the water block (inside). They offer more surface area that way.

Their designs are limited by the tool though, so you can forget about the finned, diamond island. (nice idea though).

Thanks for the link TiTch, I'm glad to see some more people come around (to the dark side?!?)

For bigben2k:

Agreed, glad to see this doesn't turn into some kind of flamewar. I like good discussions (even if I end up being wrong, at least I can learn something from it).

If I had my choice, I would setup the following Systems and conduct these tests...

- One AMD (AthlonXP) and one P4 (Northwood) so everyone could be happy.

- Roundup the leading blocks (probably about a dozen or so I could think of, but more would show up I'm sure). Same with the Radiators, and Pumps.

- Miscellaneous items might include a couple Reservoir's (some pumps would no doubt be inline as well but there are reservoirs for the Eheim pumps too). As well as different size tubing (for the different blocks and Rad's. as well as some elbows, Y's, T's and Valves.

- Some Mid-Full tower case, but remove all the case fans except the one that is in the powersupply (of course most people have at least one case fan in their systems, so maybe leave one in:) ).

- You would of course need the hottest CPU's of the moment (AthlonXP 2100+, P4 2.53 standard speed in one test, overclocked in the other). I suppose you could use some kind of CPU simulator but I perfer the real thing (plus to simulate the XP you would have to have a device with the same dimensions as the CPU core to have a valid test).

- Once you put together the system (just like you would if you were putting the system in your case, but again everyone's case is different so this could have an impact on the tests as well, but more on this in a moment). Install your ideal of the perfect system, this would be your baseline system (Maze3, BIX, Eheim 1250 pump perhaps), which would probably change after you finished your testing depending upon your results (by change I would mean that you would probably use the best components after you tested everything as your base system - Just like most people would use the SK6 as their base system when testing new aircoolers).

- Testing could include recording the temps at Idle, with a moderate load (Websurfing, gaming for an hour, etc), and with a full load (Folding@home, Prime95, etc).

- First test would be the CPU blocks, swap out each block after the test (of course after a cool down period, etc so the tests are even). You would also record all the pertinent details before and during each test (room temp, water temp, cpu temp, etc).

- the second part of the tests would involve swaping out the Radiators. Instead of a BIX use a heater core, and perform the tests on each block again.

- The next test might involve swaping the pumps (perhaps have a set of low, med, and high volume pumps) and redo the CPU, and then the radiator tests).

- What about the variables in the test you ask, like tubing size/length, and number of 90degree bends. Well you could further separate the tests into two sections, one group with a small tube (3/8 OD) the other with a large size tube (5/8 OD). As for the Elbows, perhaps use a minimum on the initial tests, and after you finish and have your new Baseline system, you could show the effect of adding more elbows to a system. You would also be able to test the effects of systems with reservoirs as opposed to those without (and wether it makes a difference performance wise or not).


Ok, if you read this far (and I probably missed something) what you may notice is that there will be a ton of tests (hundreds depending on the amount of equipment you have to test). So you might want to just test 6 or 8 blocks at a time with maybe 3 or 4 different Rad's and 3 or 4 pumps. As you would finish the tests, you would have a clearer picture of which grouping of equipment performed the best (so you would have a baseline system for your next set of tests, a so called high water mark to beat).

Eventually you would have a set of equipment that through this testing performs the best, you would also have tons of details that would set this review apart from the rest on the net. You could further break it down like the best 3/8 OD setup, the best 5/8 OD setup, the best of the smallest Rad's and biggest Rad's, as well as which blocks performed best with each setup.

What would be funny (unless you were the one to do all this testing:cry: ), would be that if the difference between the best of each category, was only 1-2degrees.

Anyway, I have probably driven lots of people away from this particular topic with all the reading, but I do appreciate all the feedback, and opinions.

I bet you will be sorely disappointed in my waterblock testing then because there will be:

No computer running in a case
No multiple radiators
No different tubing/fitting sizes
No hottest running CPUs (I need a ceramic base AMD with Palomino core to validate my diode numbers and the best I can muster is ~ 75W)

I remain unconvinced that there is any real purpose other than busy work to the majority of these studies that you want to see, Powerhouse. If you vary the flow rate (and thus the pressure capabilities of your pump) then you simulate the effects of different pumps and different rad and fitting combinations as they relate to waterblock performance (water velocity vs. pressure drop is all that matters). There is no need for anything else. The radiator is for now a necessary evil (I have no recirculating water bath) so I will use the biggest best heatercore I can find.

You have spent several thousand on equipment: 2 motherboards and high speed processors, a case, all these radiators, fittings, tubing, pumps, waterblocks, etc, and then you will learn what? Using typical overclocker temperature monitoring gear you would need a temperature difference of more than 4.5C to be valid when rating performance (2 thermistors with 3C accuracy so the error propagation goes like (3^2+3^2)^1/2 or square root of 18 for relative error in measurement). It would take several months to do the testing that you want to see, and in the end you would get a skewed vision of the true performance of the blocks because you have inextricably tied them into the pump and radiator and overall system.

What you are proposing is fine if you want to test complete kits available on the web, but it will do nothing to improve the overall knowledge level of the reader or the advance the quality of waterblock design. Idle hands are the devil's work, however.

some comments from someone who has bought a lot of test equipment, done a bunch of testing, and then upgraded the equipment to start the cycle again, several times - and it is ongoing

I would suggest that the goal be clearly identified, and the experiment designed accordingly
the methodology used must yield data that answer the experimental goal
and the equipment used must have the capability of producing accurate and repeatable results

I state the obvious as it is apparent that some are not familiar with the 'design of experiments'
if one wishes to quantify a system's performance, then that is what is tested
if however one wishes to quantify the capability of a component, then the individual unit should be tested in isolation from the effects of limitations imposed by other parts of the system
-> this is the purpose of bench testing
(a simplistic analogy would be running an engine on a dyno vs. running the car on the track)

given that it is desired to quantify the capability of a component, what are the appropriate tests ?
since wbs are the topic of the day, and several are reported to be starting test programs, lets consider how such a program could be setup

the first step is to identify those use factors impacting wb performance
then to approximate the range of those conditions
then to identify the equipment necessary to create that range of conditions
then to identify the instrumentation necessary to quantify the actual conditions at that moment of testing
and finally to develop a written procedure (or checklist) so that all variables will be addressed in the same way each and every time
-> obviously detailed records must be kept both for data analysis, and more importantly, to be able to re-create a specific setup when some data 'won't fit' - to be able to retest

now this is a chore for component testing, it is a HUGE chore for systems testing

returning to wbs, what are the salient variables ?
specimen preparation (bp flatness and finish - how to quantify ?)
connection bore dia (stock, modified)
coolant flow (accuracy required)
pressure drop vs. flow rate
coolant temp (accuracy required)
heat source area
applied power (How Quantified ?, this is extremely crucial)
goop application (how thick ? - how do you know ? - did you measure ? -> big problem here)
clamping force (must be quantified, with numbers)
influence of ambient temp and air movement
die temp (the biggest problem of all)

quite a list
and any 'tester' who does not address each of these variables (one way or another) is ignorant, or a bull shitter
(feel free to quote me)

moving right along here
what equipment, with what degree of accuracy, is necessary to quantify these variables
different testers will have different 'standards', and budgets
but each of those variables listed needs to be quantified

pHaestus has commented on accuracy, and has discussed an article illustrating error propagation in calculations
I hope he does write this (soon !) as there are too many without the technical background to appreciate what constitutes a 'good' number
accuracy and resolution are not the same, and without some method of calibration its all make believe

do look at a tester's equipment list, and see what is said about calibration

all thermodynamic testing is 'touchy', and with the very small components WCers use the measurement increment is small as well
low resolution uncalibrated equipment can totally mask, or misrepresent, what we might think are 'significant' differences between units

almost forgot to mention that enough trials should be run to establish confidence in the results

testing is not so easy
BillA

EDIT: added pressure drop to wb variables

Thanks BillA. I was going to order what we've been talking about, but you did that for us!

The most important points that you've stated are related to documentation, methodology and consistency.

You didn't mention two more variables, and I've been meaning to bring them up for a while:

1-Nature of coolant: who ever said that water alone was the only coolant? I plan to try windshield wiper fluid (water+methanol)

2-Using a Peltier: this could turn into a discussion of its own. Does the waterblock need to be designed the same way?

Given the above, the number of combinations required for testing, under PowerHouse's specs, would be astounding.

As you also pointed out, thermodynamic testing is touchy. There are a great number of variables in such tests and so, everything should be controlled, measured and documented. I had this idea that in order to isolate the outside elements while testing a waterblock, that it should be isolated in a box, but then remembered that heat would accumulate within that box, and skew results. So I thought about venting the box but that too would skew the results. So I'm thinking that this needs a lot more thought.:D

My thoughts on the testing variables of a waterblock:

1-specimen preparation (bp flatness and finish - how to quantify ?)
TH:Usually, flatness is measured in microns, where 25 micron surface ripple is considered pretty well lapped. However, I believe that the block should only be lapped if the product is sold with instructions to lap it, or if it is in obvious need of lapping.

2-connection bore dia (stock, modified)
Needs to be measured and noted, but otherwise a wb would be tested at different flow rates, regardless of this.

3-coolant flow (accuracy required)
Measured and noted.

4-coolant temp (accuracy required)
Measured and noted.

5-heat source area
Measured and noted.

6-applied power (How Quantified ?, this is extremely crucial)
Measured in Watts, as a calculation of the voltage and current applied to a high power resistor, mounted to a plate to simulate a CPU (see www.dansdata.com)

7-goop application (how thick ? - how do you know ? - did you measure ? -> big problem here)
Using item in 6, I believe that it only needs to be noted.

8-clamping force (must be quantified, with numbers)
As I've mentionned in an earlier post, the mounting hardware that comes with a waterblock should probably be used, but if it is suspected that it may not be appropriate, then it could be substituted. This is really a subjective point, as waterblocks have different mounts, which may or may not be inter-changeable. Overall, the AMD specification should be considered.

9-influence of ambient temp and air movement
Measured and noted, along with humidity.

10-die temp (the biggest problem of all)
Using a test item (such as in 6), temp should be easily measured.

BigBen2k:

You trivialize understanding the true power (heat load) that is placed into the baseplate of the waterblock. Secondary losses, variation in the applied voltage (better use a line smoother of some sort), and flaws in the insulation become a huge issue. Trying to get the accuracy of the temperature measurements to where you want them is useless unless the input heat can be quantified equally well. Contrary to popular belief ("just use a really hot CPU"), the confidence in the numbers that come from a resistor or a CPU doesn't improve (IMO) with a bigger heat load. Instead, the likelihood that differences in temperature readings can be seen by your equipment may improve. This seems like a good thing, but if the temeprature difference is due to fluctuation in the house's power (maybe someone turned on the blow dryer in my apartment) then it can lead to very incorrect interpretation.

bigben2k
well, you're listening at least - but you'll find it hard to actually do

you are dead wrong about 'power'

try this thread
and DO READ Cathar's references
I repeat: you are dead wrong about 'power'

and I overlooked the pressure drop across the wb as a parameter that must be measured with the flow rate

Different versions of Radiate report different numbers. This in itself is troubling. To further complicate matters, some sites calculate a CPU's wattage with an equation that is a ratio of stock to overclocked speed and voltage. So for example a TBird 1.4 at 1.75V will have a different output than a TBird 1.0 with its bridges adjusted to run at 1.4 and 1.75V. Troubling again. Further complication is the assumption that fsb doesn't affect anything and only raw MHz matters in heat output. Is this valid? I dunno (any takers?). There is a pretty good read at benchtest.com on this topic:

http://www.benchtest.com/calc.html

Look at the Stress Test section. His estimate is around 88% of theoretical load (not so far off from Cathar's 81%). My new and improved diode reader should be here next week with 0.125C resolution. I will posthaste compare different "100% CPU load" programs.

AMD has programs that will actually load a CPU to 100% (their words not mine) but they aren't sharing. :(

Ok, after reading the last three posts, this looks more like a Doctorate Thesis, than it does a review on WaterBlocks.:eek:

Don't get me wrong, I'm sure that if and when you figure out how to test WaterBlocks (with the degree of accuracy you have listed) that no doubt you will have a great deal of information to provide for your readers. However, I believe the vast Majority of people will skip all of your hard work, and go straight to the conclusions as most people don't really care about Applied Power, Clamping Force, Thermodynamic testing, etc. This of course is my opinion, but I would say from the lack of others posts in this thread, that I'm probably correct.

If after all your testing, you are off by a less than a degree, who cares. It's not like the people reading your eventual review will have the same conditions in which you tested anyway. What I and others want to know is, which watercooling equipment would give me the best performance (to further overclock my system as that is really the point of watercooling isn't it).

Hope I'm not sounding too harsh, but these posts remind me too much of college lectures on stuff I could care less about. I'm a bottom line kind of guy, I don't mind reading information that I can use (which waterblock clamps onto the CPU the easiest, which has the best tube connectors, etc), but your methods of testing are far to rigid for my tastes.

lol

this from the fellow who posted pages on testing
but when push comes to shove, its all too difficult

there is a classic '50s English study which concluded that comprehension was inversly related to complexity
(in dumbspeak: few understand complex issues)

hence we have priests and politicians to tell us what is right and what we may do

ain't no Intel in this box

be cool

U Know power house is right about that.

U take an average "KID" who islooking to buy watercooling parts. Send him to a 30 page site on how the testing was done, and with what equpitment, and such, all he is going to do is keep hitting next, untill he gets to that graph that shows what block came out ontop, and not give a flying flip how the testing was done, or know that the testing may or maynot simulate the blocks true preformance on his overvolted duron 950. With DD cooling cube and 2 80 mm fans. Nor will he be able to comprehend most of the data supplided with the test. Alot of you guys are employed in this feild in one way or another, may it be working in a lab enviorment or, consumer testing, but the knowledge of most of the peopl on this thread, shows that you have a great knowledge of lab, and feild testing. Which is a good thing. maybe for some, to good of a thing. But please do me this one thing. Make your results ina format that is easy for the LAMAH to understand. Buecause if I am not mistaken, that is mostly your target group. (Fell that eplaining test data to a target group, should be included in the testing procedures as a MUST) If you complile all this data, and present it to say a 3rd grader, is he going to understand the data? No, but he will understand a Hot frying pan and a drop of water. See where I am going with this.

Keep it up guys, between your minds, we should see alot of good testing.

thanks
Fix

hahahahaha, i agree :p but accuracy and precision are impoortant. Fix also has a point, having all this data is good, but it would cretainly be easier to understand if you summarized whats going on instead of just giving us a graph and letting us come to our own (potentially wrong) conclusions..

methinks a CPU 'simulator' (kinda like what Frosty Tech uses to test HSFs) would be more consistent and more precise than using a MoBo and CPU.

i also think my eyes are about to fall out after reading all these essay-length posts

:drool:

ok, Fixittt does have a very valid observation

the presentation should be sufficiently straightforward that it can be understood also by those without a great deal of technical expertise

but such simplification needs to be done after the testing, not before

so if one wishes to discuss (good) testing, sorry but it will necessiate some rigor
(feelgood kinda stuff I'll leave to others)

Cyco-Dude (in case you've not seen them)
heat die simulators here and here

Well, I'm glad that someone picked up on my momentary lapse of reason, about power. I was thinking about it throughout the day, when I realized that what I wrote made no sense whatsoever.

But I don't think I'm very far off.

All in all, the lab condition should simulate, as closely (but reasonably) that of a PC. I think that we all agree there.

Using a high power resistor, and mounting it to some plate, the size of a CPU, is one way to achieve consistency in results, but it certainly is not a proposition that simulates a PC by recreating the power output of a CPU, and that power definitely cannot be simply calculated as I stated above (P=VI). (but I do believe that with the right power supply, the voltage spikes/drops would not be a factor).

Back to square one.

How do we simulate a CPU? How do we reproduce the power that a CPU generates? How do we measure that power? Should we consider max power, or average power? Should we test for max power +25% ? If all we're calculating is the heat transfer rate of a waterblock, is any of this relevant? What about water temp?

How do we deal with the other factors that dissipate power, beyond the waterblock (i.e. CPU to air, CPU to socket, ventilation, etc...)?

Can we do this cheaper than using a CPU and mobo? How does AMD do these tests?

And as unregistered pointed out (BillA?), there is even more info that we've mentionned (although, I will point out, I did refer to some of them, just not directly).:p
1-Total system heat capacity
as discussed here:
http://forums.overclockers.com.au/sh...threadid=60614
(Hello Aussies!)
This goes back to my point that some people believe that starting up a system, then noting data right away, or only after a few minutes, is acurate, when really, it's not. In short, heat accumulates in every single component, and is dissipated by each one of those components at different rates. (that's why I'm considering finned copper tubing).

2-Pressure drop across the waterblock: yes, it exists. yes it is a factor (and should be measured), but most importantly, it is a result of the flow rate used in the test. Knowing that info though, would help greatly in selecting a proper pump. I've always said that the waterblock is by far the biggest flow restrictor (unless the tubing is innapropriately sized, but I'm assuming otherwise).

Fixitt: you're right about the lengthy report not being fully read/understood, but the report doesn't have to have all that info in the main text, but should have references. The conclusion of the report should be able to satisfy just about anybody. As to why someone would take the time to write all that up, that's a personal issue.

PowerHouse is right, in that the objective of writing/testing anything is to be able to tell the average bloke which pieces he should get, and telling him what he needs to know. If PowerHouse (I'll use you as our "average bloke") doesn't understand the purpose of clamping, then he'll need to know, and how to do it.

The results to the tests could be posted in a table, in this form:
WATERBLOCKS
a)C/W
b) optimal gph
c) psi drop@that gph.

RADIATORS
a) heat dissipation rate (graph?)
b) optimal gph
c) psi drop at that gph
d) optimal air flow (graph?)

and so on. Knowing that info, any Joe, could mix and match, according to his budget. (The above is a proposition, is not complete, and is meant to spark the discussion about how to post results). Sorry PowerHouse, but telling you specifically which rig to get, could only bring on a number of liabilities: I'd rather give you the figures, and let you choose, that way, I'm not going to get sued!

PowerHouse: The purpose of water-cooling is not always for overclock. Some people just want to water cool to reduce the noise. If you are watercooling to overclock, then you would more than likely be using a thermo couple as well (otherwise, what's the point?).

If results posted are accurate to +/- 1 degree, then that may work, as long as the differences between the items tested are not within that range!

Better move C/W way down (off?) that list, as the whole power issue rears its head again (with a vengeance now). Bet you can guess I was going to say that after reading that thread? There are always tradeoffs; best plan is to simply address them.

There are some advantages and disadvantages of both the simulators you propose and actual CPUs:

Regarding testing with actual processors, the advantage is that you actually have a "realistic" load for the waterblock to deal with, with its dimensions and material and heat release pattern being consistent. Disadvantages are myriad: You don't actually know the heat load, you have difficulties in measuring the temperature with any accuracy, you have to contend with secondary heat losses and cooling pathways that complicate precise determination of a waterblock's performance.

Wait though that last one is REAL cooling that is relevant. Processor temperatures can be collected with a reasonable degree of accuracy with a carefully calibrated diode reader (no mobos), and the processor heat load can hopefully be ballparked better than currently done (how well? I hope AMD will respond to my e-mails). This is where I am headed right now, as there are issues with the simulators (and cost) that I can't surmount at the moment. Prevailing wisdom for testing is to crank the voltage and MHz, but if I can get more reliable heat load numbers from AMD for 1.75V and 1200MHz than I can for 2.0V and 1400MHz then shouldn't I go with the speed that improves certainty in heat input? Comments? I am also guessing that perhaps someone with a good simulator might be willing to help me check my W estimates by comparison with their known power inputs (pokes Bill with a stick).

Ok onto the simulators. I don't think that the W that is coming from most of these is any better than the W coming from radiate (or similar) for CPUs; it just looks more scientifically sound and so people don't question it. Look at that o/cers au thread for my diode reader comparison with JoeC's simulator. The only conclusion is that you really aren't any more certain of the power input with a resistor type simulator than you are with a CPU so the big advantage is the use of an embedded thermocouple over a CPU diode (not that this isn't a good thing).

Gotta think carefully about what you want to know and when to cut your losses. What were we even looking at again? Which block is "best"? I forget...