Cooling Crossfire Unlocked 6950's

[Roddfather]

Hey all,

Longtime reader, first time poster. Here's my deal. I'm moving to crossfire and I am building this:

Motherboard: GIGABYTE GA-990FXA-UD3 AM3+ http://www.newegg.com/Product/Product.aspx?Item=N82E16813128514
Case: COOLER MASTER CM Storm Series Trooper http://www.newegg.com/Product/Product.aspx?Item=N82E16811119245
Graphics cards: Diamond HD6950 2GB http://www.frys.com/product/6490922;jsessionid=QJDHvT0-4XzXhMQmVwhVVw__.node3?site=sr:SEARCH:MAIN_RSLT_PG

The graphics cards are both flashed to 6970 specs and running at stock 6970 speeds.

These are my questions:

1. These cards are reference design and blow hot air out the back, but I am worried about heat dissipation, especially for the top card. I read somewhere (can't remember where) that I need to use the top PCIE 2.0 slots for 16x speed. Do I need to worry about the heat for the top card? If so, would case fan on the side panel help keep temps at a reasonable level?

2. If air cooling helps, any suggestions on fan placement (I am clueless and any help to a faq/article regarding case air flow would be much appreciated).

Thanks for any help offered!

 

[rolli59]

1 side panel fan will help the top card.
2 http://www.tomshardware.com/reviews/cooling-air-pressure-heatsink,3058.html
http://www.tomshardware.com/reviews/cooling-airflow-heatsink,3053.html

 

[refillable]

make sure you let some space in the middle of the card and install side fans as much as possible.

 

[Rockdpm]

+1, i use the same case, and i am doing a SLI setup, and Side fans on the side panel have helped temps. My top card was idling at about 37 before i got the new CM Storm Trooper. after i got the case, my idle temps became anywhere from 31-34C. i had to flip my reference card and ASUS DCII cards, so the ASUS dual fan one was on top, and the bottom single fan card was on the bottom

 

[Roddfather]

@rolli59 Thnaks for the links, very informative!

@Rockdpm Thanks on the specs for your setup. If you don't mind me asking, what size fans are you using on the side panels? I am installing a water cooler for my cpu so I was thinking of moving my 140mm fan to the side of my gpu's and blowing air on them. At least I think that is right. Would u suggest getting a bigger fan or multiple smaller fans if just one 140 isn't enough?

 

[rolli59]

1 140mm will do the job!

 

[Roddfather]

Awesome, thanks!

 

[Roddfather]

Best answer selected by Roddfather.