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So I've been a little confused about my computer temperatures, so I decided to dig into some Martin and Skinnee graphs to try and figure it out. I thought I might as well post my thought process.

Martin and Skinnee data taken from these places...

http://daemonkin.hubpages.com/hub/Choosing-a-radiator-for-pc-watercooling#

http://martinsliquidlab.org/2012/04/09/hardware-labs-gtx-360-radiator/4/

http://martinsliquidlab.org/2012/12/22/xspc-ex360-radiator/4/

I have:

1 Xinruilian 140mm fan on an ex140 rad (as intake)

2 Bitfenix 120mm LED spectres on a ex240 rad (as intake)

2 Bitfenix 140mm LED spectres on a ex 280 rad (as exhaust)

The Xinruilian runs at 1350 rpm max

the spectres do 1200 rpm max

A 360mm rad has an area of 120X120X3 = 43200

My setup has a radiator area of 120X120X2 + 140X140X2 = 68000 at 1200 rpm

and 140X140X1 = 19600 at 1350 rpm

So at max capacity at a delta T of 10C and using Martin's graphs (assuming fans are essentially the same at a given rpm for simplicity):

A ex360 dissipates approximately 165 watts at 1200 rpm

and about 180 watts at 1350 rpm

So my heat dissipation to achieve Delta T 10C should be...

165W * (68000/43200) = 260W

180W * (19600/43200) = 82W

or 342 Watts

According to Skinnee with a delta T of 10C I should get (assuming thermochill PA120 rads are about the same as ex ones)...

An PA120 dissipates somewhere between 360 and 490 watts. So using 425 for the 1200s and 475 for the 1350 I get...

425 * 1.57 = 669 Watts

475 * 0.454 = 216 Watts

or 885 Watts

A little confusing...

So in reality I am cooling a 2x7950 overclocked to 1050/1450 and a 3770k at 4.4ghz which according to my Kill-a-watt gives me 650ish watts at full load on the GPUs (litecoin mining). I added some pics below. The 280 at the top is exhaust which might be throwing stuff off a little bit.

So my delta Ts are well over 10C...currently about 25C = water temp - air temp. So not to knock on Skinnee at all, but it seems my temperatures are more in line with Martin's data. I can't get to Skinnee Labs original articles so it is hard to say if any other differences in testing that are causing the discrepancy. According to that graph though, I should be able to cool 1000 or so watts with a dT of 25C and a 360mm rad.

According to Martin, In order to cool to 10C delta I need about 250 watts more cooling or double the amount of radiator space so my 25C delta is actually not too bad (at least relative to what I thought when I first saw Skinnee's graph)