What happend to the Nexxos XP review?

[Blackeagle]

Originally Posted by Cathar

The simulator I have allows for varied CPU heat, GPU blocks and varied GPU heat, the impact of pump heat, and radiators. The only thing it doesn't really do is pre-determine the system resistance and measure that against a pump PQ curve. That bit is still manual.

Then I'll look forward to seeing it a good deal. That'll be a heck of a time saver!

[psychofunk]

Originally Posted by Cathar

The simulator I have allows for varied CPU heat, GPU blocks and varied GPU heat, the impact of pump heat, and radiators. The only thing it doesn't really do is pre-determine the system resistance and measure that against a pump PQ curve. That bit is still manual.

I hope you will let us sneek a few peeks from time to time. BTW thanks to all you guys, phaes, cathar, joe, bill for keepin everyone honest and all the others who I don't know, that do all this hard work. The brain damage is much appreciated by myself and I am sure others. I'm sure it is very often a thankless job so thanks.

Jerry

[ElDuque]

Phaestus tests are with a dual heatercore so i don't know why you say the g4 is better when having in count the whole picture, I would understand you to say other blocks will perform worst with the xp in the loop, but from what I can see, restriction don't keep the XP to perform better till 1gpm, but sure im missing something.

[Cathar]

Originally Posted by ElDuque

Phaestus tests are with a dual heatercore ... but from what I can see, restriction don't keep the XP to perform better till 1gpm, but sure im missing something.

You are missing something. Phaestus reports the temperature difference between the waterblock inlet, and the CPU. This removes the effect of the radiator from the temperatures.

Also, what you see plotted are straight temperature vs flow rate graphs. What you do not see is whether or not it is easy to achieve the flow rates being shown. This is determined by the waterblock's level of flow resistance.

Yes, straight up at 1gpm the XP is front of most any other block if those other blocks are forced to be run at 1gpm. However if you took a pump like an MCP600 (AquaXtreme 50Z) which is what it would take to give you 1.05gpm flow rates with the XP in a full 1/2" tubed system, you would then be seeing 1.3gpm with a Storm, or even 1.6gpm with a Swiftech MCW6000. The other blocks allow more flow through given the same pump. They will be a lot further along on their flow performance curves than 1gpm.

i.e. You can't just look at the 1gpm flow rate and say "this block is better". You need to look at what it takes to achieve 1gpm flow rates with a certain block with an actual pump/radiator/tubing combination, and then compare that with what the flow rates would be with a different block and the same pump/radiator/tubing.

[Edit: Corrected flow rates. Can't even read my own graphs. ]

[psychofunk]

Originally Posted by Cathar

....Phaestus reports the temperature difference between the waterblock inlet, and the CPU.

I Don't know the ins and outs of it but seems that knowing the diff between ambient and cpu temp might be cool too. Or am I missing it, please don't tell me it is already there. And if it is tell me how to figure it out. Thanks.

Originally Posted by Cathar

Yes, straight up at 1gpm the XP is front of most any other block if those blocks are run at 1gpm. However if you took a pump like an MCP600 (AquaXtreme 50Z) which is what it would take to give you 1gpm flow rates with the XP in a full 1/2" tubed system, you would then be seeing 1.5gpm with a Storm, or even 1.9gpm with a Swiftech MCW6000

Can you tell me how you came up with those flow rates. I want to learn so please if it is not too much trouble. Even a PM if it is like adding 2+2 for everyone around here. Thanks.

[Cathar]

Originally Posted by psychofunk

Can you tell me how you came up with those flow rates. I want to learn so please if it is not too much trouble. Even a PM if it is like adding 2+2 for everyone around here. Thanks.

http://www.employees.org/~slf/curves...p-mcw6-gpm.png

http://www.employees.org/~slf/curves...4g5flowgpm.png

Follow a block curve up from the bottom left. Where it interesects a pump's PQ line (they start at the upper left and curve down to the lower right) is what the predicted flow rate will be. All those curves assume a Thermochill 120.2 heatercore with ~10.5mm ID barbs, and 2 meters of 1/2" tubing.

[Cathar]

Oops - misread the Storm and MCW6000 flow rates. Corrected my post above.

[psychofunk]

Originally Posted by Cathar

http://www.employees.org/~slf/curves...p-mcw6-gpm.png

http://www.employees.org/~slf/curves...4g5flowgpm.png

Follow a block curve up from the bottom left. Where it interesects a pump's PQ line (they start at the upper left and curve down to the lower right) is what the predicted flow rate will be. All those curves assume a Thermochill 120.2 heatercore with ~10.5mm ID barbs, and 2 meters of 1/2" tubing.

The curve for the nexxos, is that a guesstimation? How did you figure what the curve would be like? Please forgive if that is a stupid question.

[ElDuque]

but is that extra flow really useful in a loop with reservoir? with a reservoir the pump has no restrictions to get water, so the flow rate through the radiator and at the waterblocks inlet would be about the same? I mean more water in the reservoir doesnt mean the pump will use it. But sure i'm missing something xD

Excuse my english.

[Cathar]

Originally Posted by psychofunk

The curve for the nexxos, is that a guesstimation? How did you figure what the curve would be like? Please forgive if that is a stupid question.

I had the XP here and measured its pressure drop.

Storm G4 and G5 blocks were also as measured by me.

Swiftech MCW6000 is taken from an extrapolation of OC.com data, and also from correlating it with Phaestus's peak flow data for which the MCW6000 near exactly matches the Cascade SS.

So yeah, all of those curves are pretty accurate, with the slight provision that the MCW6000 curve may be a slightly off as I drew that from OC.com and Phaestus.

[Cathar]

Originally Posted by ElDuque

but is that extra flow really useful in a loop with reservoir? with a reservoir the pump has no restrictions to get water, so the flow rate through the radiator and at the waterblocks inlet would be about the same? I mean more water in the reservoir doesnt mean the pump will use it. But sure i'm missing something xD

Not sure where you are coming from.

Will repeat it again.

Given a pump, and a waterblock and a radiator and some tubing, the flow rate (litres per minute) is determined by the level of resistance to flow that the pump has to work against.

If we change the waterblock for a less resistive one, the flow rates (litres per minute) will go up.

If we look at the flow rate vs performance curves, the first block will have less litres per minute (or gallons per minute) moving through it than the second block.

It's the number of litres per minute that determines which point you need to read off the flow vs performance graph.

The flow rates are not equal for different blocks when given the same pump. You cannot assume that they are equal.

Having a reservoir doesn't change things.

[psychofunk]

Originally Posted by Cathar

I had the XP here and measured its pressure drop.

You mention pressure drop, is there a way to plot a similar graph based on the pressure drop information at Overclockers.com ? Just something to get in the ballpark?

[Cathar]

Originally Posted by psychofunk

You mention pressure drop, is there a way to plot a similar graph based on the pressure drop information at Overclockers.com ? Just something to get in the ballpark?

To do it properly you really need to measure it.

For a "ballpark" though. Classic flow mechanics tells us that the level of flow resistance is proportional to the flow rate squared (P = Q ^ 2). This doesn't take into account turbulence and boundary layer conditions though.

For a fairly decent ballpark equation to extrapolate from OC.com's results I've personally found that P = Q ^ 1.85 offers a pretty decent approximation across the typical range of flow rates seen in water-cooling. P = pressure. Q = flow. Not as ideal as having real data, but when given a single pressure/flow point like OC.com I personally found it to give a fairly close ballpark curve.

[BalefireX]

So (using reasonably large levels of guesstimation combining Cathar's pressure drop/pump graphs with pH's testing and ignoring the differing heat inputs of these pumps) these are the (highly) approximate numbers I come up with:

Eheim 1046: G4= ~10.1° MCW6000A= ~10.5º NexXxoS XP= ~10.6°
Eheim 1048: G4= ~9.6° NexXxoS XP= ~9.9° MCW6000A= ~10.1°
MCP-600: G4= ~8.9° NexXxoS XP= ~9.3° MCW6000A = ~9.8°
MD20RZ 60hz: G4 = ~8.2° NexXxoS XP= ~8.7º MCW6000A = ~9.4° (very guesstimated)

That look reasonably right to anyone else?

//Edit: posted and then instantly realized I wasn't taking into account the difference increased flow makes on the radiator. Numbers are most likely worthless therefore.

[leejsmith]

Some pics of the XP from madshrimps

//edit by pHaestus: Madshrimps.be no longer allows referrals from this site. Instead they forward our readers to some page about gay men in musicals. This is causing people to be insulted on this site; I find this to be childish, pointless, and I suggest that, if it also upsets you, that you complain to the companies that advertise and sponsor their website.

[pHaestus]

That review is a pretty large improvement in legibility over L3D's earlier works. It's really criminal to let him be both author and editor though; he is pretty clearly unable to succinctly say anything. The thermodynamics primer is a classic example. It's technically correct, not of any real relevance, and exists purely to make madshrimps readers think that our friend L3D is an expert. Are we to assume that, from his primer, he has now added the plume of "thermodynamics master" to his chapeau? Perhaps not:

"The NexXxos XP was designed for optimal performance in a "low-flow" environment"

Contrary to what people often visualize, the idea that a wb can perform optimally at low flow rates is balderdash. Increasing flow increases water velocity. Increased water velocity will increase disorder (turbulence) and decrease boundary layer thickness at the block/water interface. These increases improve transfer of heat (via forced convective cooling) between the coolant and the block.

Furthermore the NexXxoS XP is highly flow rate dependent (as you can see in the graph I posted) so I don't even know where L3D is coming from. Just parroting back something he read somewhere I guess. Or he perhaps figured the strategy of "always disagree with Procooling writers" approach had been working so well in the past that he should stick with it.

Even still it's a lot better than his previous body of work. I still think that a multipage wb review is silly, though.

[Liquid3D]

Originally I came to this site hoping to expand my knowledge, and I also believed as an "authority" on the subject you might act the role bestowed upon you. So I was taken aback when that original thread went well beyond any semblance of criticism, degrading into a flaming session. Even if the review was poorly written which it was, in theory being more experienced one would expect more from you. Harboring this, and other attacks upon me from this site, which went way beyond decent (or constructive) criticism, led to the Xtreme Thread. Regardless of what you may think that was not a statement as to the validity of your test methods, although it could have been worded much better.

I try to meet people half-way, in our case I thought I went two-thirds of the way to attempt to make peace. Perhaps in this respect we differ. What you don't know about me, yet adamantly and continually presume is what bothers me. I do not consider myself an authority, nor an expert in the fields of thermodyamics or watercooling. What I am, is eager to learn and willing to work very hard at it. I research everything from multiple sources, and no matter what I read or write I remain teachable. Anyone who believes they know all there is to know on a given subject, is closed minded by default. When you refer to research as "parroting" this presumes you weren't taught anything, but were simply endowed with watercooling knowledge at birth. Have you ever repeated a theory, or a formula? What if someone labled that parroting?

I do not take the opposite view from ProCooling based on harboring anger for this site. It's the argument in general not the author. And I wish more people could seperate the person from a specific theory they hold to be true. People change, they grow (hopefully) some regress, but people do change as they gain experience. Despite the motivation, I've learned from criticisms and insults alike deriving from this site. For example testing by an open window, was silly, as was relyng on motherboard diodes for temp readings. In fact I've even placed my system on a table, lifting it off the floor.

So this review is lacking, and I was in disagreement about how the results were published, wanting the ambient, and idle temperatures included. And while you claim I can't "succintly say anything," I included the thermodynamic explanation because there are those out there I thought might appreciate it. I really love this hobby, and I enjoy the challenge of writing an interesting and thought provoking review. I try to engage the reader instead of simply providing raw data. Where one page reviews are concerned, isn't it then possible you could be replaced by manufacturer specifications? If the manufactuer was honest, (I would hope most are) anyone could then simply compare spec's? So what would be the point in reading a "dry" 1.pg watercooling review, if we could glean the same data comparing spec sheets?

Well your 1.pg reviews are definately valuable. I'm still working on improving my test methodology, as well as my writing skills, eliminating potential fodder. My motivation for writing this was your humanity in not flaming the review simply because it was written by me. This indicates there's a somewhat reasonable person in there. And for that I'd say this critique of my review is a "pretty large improvement" over your earlier comments. I hope some day we can put this animosity behind us.

[9mmCensor]

My philosiphy on writing reviews is.
1) Writing reviews on things you know about. If you dont know about it, LEARN it, THEN write the review. Dont write a review as a learning experiance. That would be a gross disservice to the reader.
2) If you cant write something that is accurate dont write it. This includes, things you dont know for certain are true, but improper test equipment. If you cant test something and have accurate results. Dont test it.

----

Parrorting is when you blindly accept knowledge and then tell it to the world.

Learning, is finding knowledge, questioning it, testing it, revising it, prefecting it, and finally accepting it.

[JWFokker]

Originally Posted by Cathar

Really? Once radiator performance is taken into account, and ignoring the blocks that I make, I would be more inclined to argue that for anything up to an Eheim 1250 sort of pump that the MCW6000 would be a match for the XP, with the MCW pulling a clear lead as the pumps get weaker and the rest of the setup is made more restrictive. Above the Eheim 1250, pumps like the MCP600 and better would tend to imply that either the White Water or the RBX w/ #5 nozzle would start to take over once radiator performance is factored in.

The XP is an extremely impressive block, no doubt about it, but its level of flow restriction coupled with the impact that this has on the overall picture can't be ignored - it is extremely important to consider what the radiator is doing as well, because unlike artificial testbeds people aren't using chillers/heaters to hold water to a fixed temperature.

Depending upon what pump you choose there already exists a few options on the US market today that match or exceed what the XP would do for you once the whole picture is taken into account.

For those of us interested in pure performance, we'll buy more powerful pumps for this block. Or in my case, another Mag 3 for my G4. But I suppose you're correct though, that the MCW6000/6002 will still be the block to get for the majority, who don't want to buy an Iwaki or put a couple Mag 3's in series.

[9mmCensor]

Lol, started reading this. blah blah, but that res, is a copy of the innovatek res, thats been out for ages.

page 2
you say heat = kinetic energy twice
if people reading a watercooling article dont know what conduction means, they are in trouble
no need to give photo credits in the text and on the picture.

I dont want to read this anymore...
A review is not an english essay. You are not tring to impress your professor with extra words, that jazz up your writing. It should be clear, conciese and accurate. Your writing style leads me to belive that you are compensating for something (technical ability maybe) with fancy writing.

[JWFokker]

Originally Posted by Liquid3D

So this review is lacking, and I was in disagreement about how the results were published, wanting the ambient, and idle temperatures included. And while you claim I can't "succintly say anything," I included the thermodynamic explanation because there are those out there I thought might appreciate it. I really love this hobby, and I enjoy the challenge of writing an interesting and thought provoking review. I try to engage the reader instead of simply providing raw data. Where one page reviews are concerned, isn't it then possible you could be replaced by manufacturer specifications? If the manufactuer was honest, (I would hope most are) anyone could then simply compare spec's? So what would be the point in reading a "dry" 1.pg watercooling review, if we could glean the same data comparing spec sheets?

I don't want a review to be 'though provoking'. I want it to tell me exactly what I need to know. The important information. Waterblocks are a purpose built tool. All you need are the specs for each and they're immediately comparable. I want C/W curves, head loss, size, weight, mounting pressure, etc. It doesn't matter HOW it works, just how well. Explaination of thermodynamics is superfluous to a review and should probably be reserved for educational articles. A review is for the evaluation of a given product's performance and that's all I'm looking for in a review.

And I won't rely on a manufacturer's claims. When would you expect a manufacturer admit their product is anything but the best? And they don't provide the information I need anyway. I don't recall seeing any performance stats on DangerDen's or Swiftech's websites.

[BillA]

"I don't recall seeing any performance stats on DangerDen's or Swiftech's websites."

because you are too stupid, or lazy, to look ? go to www.swiftnets.com
try hsfs, wbs, and kits; they ALL have performance numbers

and you are a prime jackass to tell me my data is biased,
or are you saying I paid off pH to produce the same results ? (mine were posted publicly before his)
all you are saying is that you would be a whore if paid (as you expect that of all others),
you would not be accepted at Swiftech, lying is cause

[JWFokker]

Lazy...yeah. I don't remember those graphs being there before, but it's been a while since I've been to the Swiftech website. Sorry.

And I'm not saying you're biased, but as a general rule I would rather rely on third party testing, which is to say I DO rely on pH's testing. I'm not sure where you got the idea that I suggested you paid him off or that you WOULD pay someone off. But regardless of whether the manufacturer is honest about performance or not, I would rather compare data taken from the same test bed (in this case, pH's) so that there's less of a possibility of uncontrollable variables.

[jaydee]

Originally Posted by leejsmith

Some pics of the XP from madshrimps

//edit by pHaestus: Madshrimps.be no longer allows referrals from this site. Instead they forward our readers to some page about gay men in musicals. This is causing people to be insulted on this site; I find this to be childish, pointless, and I suggest that, if it also upsets you, that you complain to the companies that advertise and sponsor their website.

Why is it when I click on that link I get redirected to: http://www.gettingit.com/static/inte...les_death.html ????

[pHaestus]

Looks like they made referrals from proforums point to that page. You can do the dragondrop and it works still. As for why, well who can say why jmke and co does anything?