Introduction

Hi guys!

This is my very first post here at OC forums and I figured I'd consult the best. I've been in the IT field for just over 11 years now and have built my fair share of systems but have limited experience with modified cooling. I just built a new PC and here are the specs.

Intel Quad QX6800
Dual PNY 8800GTX's Factory OC'd
Asus Striker Extreme
4GB OCZ PC8500 1066FSB

I have a situation when running my 8800's in SLI. The system seems very unstable and I have come to the conclusion that it is a thermal issue because if I remove either 8800, the system is fine. Its not the power supply because I have a Thermaltake 1000W Toughpower all connected properly regarding 12v rails, amps, etc.

Questions:

1) I am looking to cool my CPU and both GPU's. What system do you recommend? I.e. cooling blocks, reservoir, pumps, etc?

2) Is there a unit that supports two isolated water cooling circuits? One for CPU, another for GPU's?

3) If not watercooling, what is another alternative method that would be recommended? Must be practical.

I really appreciate all of your feedback and time invested to helping me resolve my issues. I was thinking the Reserator XT but I heard it's only good for one CPU. Not a CPU and two GPU's. If you guys could post the cooling equipment you would buy for my system I would really appreciate it. Thanks again.

With your specs..water cooling is probably the best option lol...
1. simple parts would be 2 swiftech MCW60's and Apogee GTX, MCP665 pump, MCR320 radiator
2. Not that i know of, if you want to do 2 loops then you will need another pump and definitely radiator..maybe even 3 if you can fit it in
3) not much choice...probably too hot for air cooling lol

Is there any budget you going on?..i can estimate how much dual loops might be

The only concern I have about those VGA blocks you listed is that they don't look like they have contact with any of the onboard VGA RAM modules..

Take a look at this block to see what I mean.
http://www.frozencpu.com/products/6...quid_Cooling_Block_ZM-GWB_8800_Ultra_GTX.html

Do you think it is necessary?

For the MCW60 you would get the MCW8800 which comes with video memory heatsinks and voltage regulator heatsinks..tho they suck at sticking lol...(i took paste off and used as5 )
But if money isnt a concern and you rather get a full block id go with Swiftech Stealth or maybe a EK block...zalman watercooling i dont think is too hot..but dont quote me on that

You don't want the Zalman block. Go with the MCW60 blocks with ramsinks. The GPU memory chips don't require that much cooling, and you won't see any improvement gains by going to a full cover block. Also, full cover blocks are a one-card deal, whereas the MCW60 should work for a few generations of GPU.

As for pump, the MCP655 is a good pump. If you are very concerned about noise, then the better option would be an MCP350/DDC3.1 coupled with a Petrastechshop top. It is the king of quiet at only 24-26db vs 33-34db for the MCP655. The MCP655 has more flow however out of the box.

You don't need two loops to cool this. One loop with the recommended parts and an MCR320 rad will cool this very well as is. Anything more is just overkill.