even better than cascade?

[l00b3r]

I'll do it if Cathar send me a Cascade and someone sends me the Murks Block

-Matt

[maxim]

i think that unregistered is gonna have to resurrect his test bed for this one. no one on this forum will believe anyone else, but BillA. it would also be a great opportunity to see how the cascade is compared to WW, since it was never tested there.

[Quickmcj]

Tommy the old wake up?

[bigben2k]

I've given myself until the end of the year, to get my testbench up and running: I'm about 1/3 of the way there. Still, it doesn't mean that I'll be up to par with the procedure!

[maxim]

bigben2k, so you wanna get WBs for x-mass to test?

[bigben2k]

Hey, now there's a good idea!

Ok, everyone who wants to send me an XMas present, PM me!

[Socko]

The cascade that they tested was not silver though. They only tested the copper version.

[Wildfrogman]

The problem wasnt that the casecade was the copper version. More a problem that the reviewer used a weak WEAK ehiem 1046 pump that just isnt enough for the casecade to really shine. Chances that the cascade with a 300~gph pump would pull ahead since the cascade depends alot on impingement~jets of water hitting the cups.

[SysCrusher]

The murk is actually a good design. I love to see how it performs with bit stronger pump. Reminds me of an Intel white paper I seen.

[Wildfrogman]

Yes, I do beleive the murk would perform much better with a larger pump also. I was just meaning to say the cascade should have more to gain in performance. But that is a good point also....we dont know exactly how good the murk works with a normal 300gph pump many use.

[Cathar]

Of course we're assuming that the testbed is producing reliable results.

Single mount testing only.

Uninsulated heating element favoring smaller footprint blocks.

Look at the results of the WCP testbed to most other trusted testing results and one can quickly see that something is strongly amiss.

[Wildfrogman]

What kind of gph were each of the waterblocks operating under with the ehiem 1046? What kind of mounting pressure were the blocks mounted under? And why did they use the ehiem 1046 of all things instead of a more standard 300~gph pump like a maxi-jet 1200, via 1300 and ehiem 1250?

[WAJ_UK]

I liked this statement:

Cathars 4xID theory isnt proved yet and google cant find anything about it...

seems like people have forgotten about that form of information printed on a thin white substance called paper. Libraries are a good source of information and usually more reliable than google.

[Cathar]

Originally Posted by WAJ_UK

I liked this statement:

"Cathars 4xID theory isnt proved yet and google cant find anything about it... "

seems like people have forgotten about that form of information printed on a thin white substance called paper. Libraries are a good source of information and usually more reliable than google.

Perhaps the most defining paper that I used to launch from for Cascade development:

http://web.mit.edu/lienhard/www/laiche.pdf

The 4xID thing isn't just a theory. There's a good deal of research behind it if one bothers to look. Things are a little bit different though due to the use of the cups. The paper also focuses on pretty high jet velocities (~45m/s) and using about 80PSI pressures.

It should be noted that I targetted the Cascade's design for 4-10LPM flow rates, or roughly 2.5->6 m/s jet nozzle velocities, and 2-10PSI pressure-drops across the block. The Cascade will continue to show good performance improvements right through that range of pressures.

If I were designing the Cascade to work well on a super low-flow testbed barely mustering 0.5PSI PD across the block, then I would have done a large number of things differently.

The test procedure followed by Phaestus, in the wake of BillA's excellent work, is a shining example of why single point testing is utterly useless. Had Phaestus decided to focus on just a 0.5GPM flow rate we'd all be left thinking that the Maze4 was a piece of crap, and the RBX is just average, and indeed this is just what the WaterCoolPlanet testbed is doing, and claiming to be able to rank the world's waterblocks. Rather interesting too is the ~2C difference between the RBX and the Cascade for Phaestus at 0.5GPM, yet just a 0.5C difference at WCP. Where'd the other 1.5C go? Oh I'm sure that it had nothing to do with mounting variances and testbed irregularities. Worse, the WCP testbed test load is quite a deal higher, so the differences should've been more like 3C, so where did the other 2.5C go that should've been there? What, though, of the RBX, Maze4 and Cascade's performance when operated within their targetted design parameters? Are such even considered, let alone explored, under such a testbed?

I've ranted enough about the WCP testbed. It just saddens me to think that people would actually choose to use it as a reference when it is such a joke.

[^catalyst]

im no crazed waterblock tester, and even i know using a 1046 to test a block like the cascade is just... silly.

[pHaestus]

well presumably when I stop mounting waterblocks like a little girl and quit using springs then I can get by with a single mount as well Cathar

[freeloadingbum]

Rather interesting too is the ~2C difference between the RBX and the Cascade for Phaestus at 0.5GPM, yet just a 0.5C difference at WCP. Where'd the other 1.5C go? Oh I'm sure that it had nothing to do with mounting variances and testbed irregularities. Worse, the WCP testbed test load is quite a deal higher, so the differences should've been more like 3C, so where did the other 2.5C go that should've been there? What, though, of the RBX, Maze4 and Cascade's performance when operated within their targetted design parameters? Are such even considered, let alone explored, under such a testbed?

The rbx was using the #5 nozzle plate. They showed the #1 plate to be about 1C worse. Plus pHaestus had alot of trouble mounting the rbx. I have a feeling that when Joe over at overclockers tests the WW that the difference at 1gpm between the rbx will be alot smaller than what pHaestus showed.

As I understand it, the german site used 100 watts, less an unknown secondary heatloss (say 5%) amount to pHaestus's 75ish watts as measured in the block. So thats 1.5C minus 1C for different nozzle, then add 20% equals .6C off the mark which could be explained by mounting variance.

This isn't to say that I'm validating the site's methods, just to say that the results aren't that impossible.

[pHaestus]

Plus pHaestus had alot of trouble mounting the rbx.

Bad mounts were thrown out rather than averaged in to skew performance numbers. Which was what made the outcry over my comments kinda funny I thought (OMG HE'S BIASED AGAINST DANGERDEN)

[freeloadingbum]

Bad mounts were thrown out rather than averaged in to skew performance numbers. Which was what made the outcry over my comments kinda funny I thought (OMG HE'S BIASED AGAINST DANGERDEN)

I understand that but I still have a hunch that Joe won't get as big as a difference. I base this on Joe's difference between the swiftech and rbx being the same as BillA's results between the swiftech and WW.

[Cathar]

Originally Posted by freeloadingbum

I understand that but I still have a hunch that Joe won't get as big as a difference. I base this on Joe's difference between the swiftech and rbx being the same as BillA's results between the swiftech and WW.

If we assess the relative differences between the MCW5000-A and the White Water between BillA and Phaestus, we see that they do correlate fairly closely.

If we assess the relative differences between JoeC and BillA at 1GPM, we do see a quite a serious anomaly, such as the SlitEdge vs the MCW50002, then there's the PolarFlo.

JoeC, to my understanding, also mounts just once. JoeC has faith in his mounting schema due to some tests he ran in the past obtaining repeatable results, and has dropped mounting blocks multiple times because of that. The right choice or not?

Phaestus's results with the Maze 4 and the RBX correlate very closely with JoeC's.

It would seem that for whatever similarities you can draw between the 3 test-beds, one can also find an anomaly.

Then we have Phaestus's testing of the Cascade yielding a mount that obtained a result more than 1C better than his average. Then we have the RBX variations which were dropped.

Even BillA yielded the odd mount with the White Water in his tests that obtained a result about 0.5C better than average.

What this tells me is that mounting blocks is bloody hard to do, even for those who are really taking care. WCP mounts just once. JoeC mounts just once.

Those who don't mount more than once won't catch variations. Those who do mount more than once typically throw away the extremes (high and low) and take an average.

Myself, I believe in assessing a block's performance on the basis of its best mount out of a large sequence of mounts (at least 12), with anything else less than that best to be considered in error, rather than considering any good mounts as anomalous.

Single mount testing, even for those who know what they're doing, is always subject to +/- 1.0C variations, no matter how firm their conviction that the truth is otherwise.

When designing a block I want to know what the design is capable of. Taking an average of mediocre mounts won't achieve that, because all you're doing is taking an average of your mounting "flaws", rather than measuring what the design can actually do.

IMO Phaestus should've used the results he got from the best mount over the sequence of 10 mounts. That's how I do my testing but it's not for me to impose my beliefs on others. What's to say that JoeC didn't "luck out" on his first mount of the RBX, and achieve an optimal mount, when many other mounts of other blocks were merely "average". My own testing, and other's testing, would indicate that to be the case, but I'm biased. I've also stated my position, so it's for people to take it however they want. I know in my testing I don't want to throw away the possibility of a good design because of mounting variances. Mounting variances can be fixed easily, but losing a good design and chasing up a wrong path is not so easy to "fix".

[pHaestus]

Cathar:

I believe that JoeC mounts multiple times, as shown here

In principle he should get less variance than Bill or I because of his clever method of mounting.

From a statistical standpoint, throwing out all mounts other than the best one is a bad idea. A medium to large sample and a mean + std dev is much more logical. We have different goals though; you want to see maximum possible performance from a block and I want to see minimum chance I am wrong about recommendations

[freeloadingbum]

If we assess the relative differences between JoeC and BillA at 1GPM, we do see a quite a serious anomaly, such as the SlitEdge vs the MCW50002, then there's the PolarFlo.

The Polarflo that Joe tested had over 2 times greater pressure that the one BillA tested so we can't expect any comparison. The slitedge results still have me confused. Hopefully pHaestus will test it shortly.

JoeC, to my understanding, also mounts just once. JoeC has faith in his mounting schema due to some tests he ran in the past obtaining repeatable results, and has dropped mounting blocks multiple times because of that. The right choice or not?

I think you're wrong here. Joe states a variance in each test, usually around .0015C/W but different each test, so he must be doing multiple mounts. I was under the impression that he was doing 4 mounts. If he's doing only one mount, then I would agree with you.

Myself, I believe in assessing a block's performance on the basis of its best mount out of a large sequence of mounts (at least 12), with anything else less than that best to be considered in error, rather than considering any good mounts as anomalous.

I agree with your best mount philosophy. It's always frustrating when someone will do multiple mounts then only show an average without saying how much variance he had or what his best mount results where.

As far as the results from the german site go, they're accurate enough to make me very curious. From what I can tell from the picture, the frontrunner looks to be just a cross drilled block, with three or four holes drilled from one barb to the other.(refering to the 1A-HV2)

Edit: changed .015c/w to .0015c/w

[Cathar]

Okay, I think I was wrong about JoeC's number of mounts.

He still has some somewhat strange data though.

From a statistical standpoint, throwing out all mounts other than the best one is a bad idea. A medium to large sample and a mean + std dev is much more logical. We have different goals though; you want to see maximum possible performance from a block and I want to see minimum chance I am wrong about recommendations

Oh, I totally understand your position and I by and large agree with it for purposes of writing a review for the common purchaser. It's just not ideal when trying to separate out design performance from "typical mount" performance.

We're striving for two different goals. For me, looking at the best results with each block is more interesting to my eye.

[Jabo]

This is quite interesting discussion going on here indeed
my 5 pennies:
Lokking at pictures and analyzing decriptions of aformentioned deustch testbed system I came to following conclusions (based on my limited knowledge of fluid mechanics and thermodynamics):

1. Heatload simulating element used (it's size and configuration) produces massive thermal energy density per mm^2. Such setup preffers blocks with thicker base plate (Fourier's law, isotropic heat diffusion etc.), which may in turn explain better performance of Murks block (VERY thick base plate)

2. Taking into account the above and low flow (jet impingement design is based on localized increase of coolant's density/pressure which entails increased thermal capacity maintaining the highest possible dT) it's totally expected that Murks performance is better then Cascade's (sudden 4C drop is simply impossible, unless Tom discovered how to dump excesive heat into another dimenssion or used sth like foamed graphite insert combined with laser beam micro channeling of copper )

3. Results are just numbers and like with all statistics one reading it has to know very well how to interpret results or not be suprissed arriving at incorrect conclusions.

To summarize, as Cathar stated above, there are no universal designs and every piece of h'ware shows it's potential only if used within it's design perameters.
My conclusion is that (apart form changing goal post mid game i.e. heatload element swap) for given setup results are correct but they do not represent anywhere near the full potential of jet impingement designs.
Its like saying that Iwaki pumps are the best but peeps seem to forget that for an 'imaginary' system with head loss below 3 meters they are outperformed by great number of much cheaper and generally considered not on par with Iwaki babies

[8-Ball]

Originally Posted by Jabo

Its like saying that Iwaki pumps are the best but peeps seem to forget that for an 'imaginary' system with head loss below 3 meters they are outperformed by great number of much cheaper and generally considered not on par with Iwaki babies

Please rephrase to an "imaginary" system with a very low restriction, since the head loss varies with flow rate. It is NOT constant.

The restriction or resistance to flow rate, is a property of a system, however, this also varies with flow rate.

The number of volts applied across an electrical circuit is not a physical property of that circuit is it. It is something we have applied, much like a head loss or pressure drop in a liquid circuit.

8-ball