Advice on Watercooling please

Hi just joined today but have been lurking and getting good advice from you all for a while now. I have recently started water cooling my rig and would like some advice. I went and purchased two MCP655 pumps thinking it moves 317GPH so two should make it a true 317GPH all around the loop? I havent tried it with one pump yet so Im not sure if this is benefiting my loop or not? Ive heard moving the water around the loop to fast will hurt my cooling because the water doesnt have enough time to pick up all the heat it can? I guess thats my first question should I use one pump or two? The other thing is I have my loop as follows triple fan Koolance radiator going to pump then my CPU -> North Bridge -> South Bridge -> 120mm radiator -> 1st Mosfet -> 2nd mosfet -> reseviour -> second pump -> 120mm Dual Pass Radiator -> 1st 8800gts 640MB -> 2nd 8800GTS 640MB video card and back to the Koolance triple fan radiator.

Now Im thinking of splitting my loop into two loops with 1 pump on each 1st loop only CPU, NB, SB, Mosfets then loop 2 only Video cards?? or keep the loop but split it CPU-Y Split one to NB-SB then the other to mosfet 1 - mosfet 2 then both back to 120mm radiator then to resivour to video cards? I will draw a simple diagram and attach it to this as I know Im probably confusing the way Im writing it down. but I would like all the advice I can get as this will be the third time I take my machine apart to reconfigure it and I want to do it the best way with what i have now. oh and Im not using water to cool it I have Fluid XP EXT non conductive liquid.


Here is what I have in my rig:
QX6850 Extreme 3.0GHz (Havent overclocked YET)
4 Gigs of Corsair XMS
P5N32E SLI Motherboard
2 WD Raptor
2 EVGA Nvidia 8800GTS 640MB Video Cards
Soundblaster XFI Sound Card

Please any help will be appreciated and I will do it on Saturday so I would like to come up with something solid by then. Let me know if you need to know anything else. Thanks!

Let me just add my temps
CPU is 1st core 50C 2nd 53C 3rd 55 4th 57C
Motherboard 35C
VGA 1 39C VGA 2 40C thats all I have checked so far

I like the dual loop idea. I don't like the dual loop #2. Not enough cooling power. But try it out it might keep em cool enough with a good CFM fan, never know.

Loop 1 in the dual loop config has a LOT of restriction. Is there any real reason to cool the SB and the mosfets? I don't. Most of us don't. I slapped a HR05 SLI passive on the SB, plenty cool! My Mosfets have air blowing on them and they stay cool. Is the flow rate good enough with all those blocks? Keep it above 1 GPM if you can.

Just thoughts pouring out, hope my Q's help. If you have all the stuff go ahead and try and teach us?

Thanks for the reply Conumdrum. I actually did read on here that the NB and SB and mosfets dont really need to be watercooled even when being OC. I decided to do it for two reasons 1. The temps on my board were way to high when I first started to water cool because I did not have any fans in my case however the mosfets had heat syncs on them but were going upwards of 70C in idle and very hot to the touch something I didnt like 2. I got the NB SB and Mosfet blocks for dirt cheap off a friend.

Can you please elaborate on what you mean by the first loop having too many restrictions? where? and at 317GPH I would think on a small loop like that it wouldnt affect it?

M4K4V3LI said:

..I went and purchased two MCP655 pumps thinking it moves 317GPH so two should make it a true 317GPH all around the loop?

...Ive heard moving the water around the loop to fast will hurt my cooling because the water doesnt have enough time to pick up all the heat it can?


Let me just add my temps
CPU is 1st core 50C 2nd 53C 3rd 55 4th 57C
Motherboard 35C
VGA 1 39C VGA 2 40C thats all I have checked so far

Click to expand...

You need to find out what a pump PQ curve is and what it tells you.
http://www.procooling.com/index.php?func=articles&disp=38&pg=1

No mater how fast or slow the water goes, it spends the same amount of time in the Rad, in the Block(s) or in the pump. If it goes for example, twice as fast, then it will come back twice as often.

Are those idle or load temps?

Here's some reading for you:
http://www.over-clock.com/ivb/index.php?showtopic=20277
http://www.overclockers.com/articles511/
http://www.xtremesystems.org/forums/showthread.php?t=77260
http://translate.google.com/transla...&article_id=222&langpair=de|en&hl=en&ie=UTF-8

And here's a spreadsheet for calculating flow rates:
http://www.xtremesystems.org/forums/showthread.php?t=151627

Thanks Billb thats a lot of great info I will read through it as soon as I get a chance. The thing about those temps are that I check them when the PC is first booted up through Nvidia monitor program then I play about an hour or so of Crysis and check them again and they are the same maybe 1 or 2C higher but they dont tend to go higher or lower then those temps by a few degrees I know some people use software to test the system and get it hot but I just use my everyday activities to monitor my temps. Should I use a program to do it? The way I see it if it can stay the same when I play Crysis for an hour and BF2 for 4 hours straight and its the same temps I should be fine am I wrong?

Playing a demanding game is a great way to test temps.

I would suppliment that with some CPU torture tests, just to get an idea of what a full 100% load on you CPU is going to look like, and what stress it will put on your system.


I prefer to use Orthos.

M4K4V3LI said:

The thing about those temps are that I check them when the PC is first booted...

...and check them again and they are the same

Click to expand...

You could try NVTempLogger, it will run a real time graph of GPU temps.
http://downloads.guru3d.com/download.php?det=1194