Another 6950, got some concerns

[insejn]

Another 6950 for xfire, got some concerns

Sorry, long post as I want people to have the full background and so I can hopefully avoid loads of questions.

So... I've been thinking about a small upgrade to my system, as I'd like to run another screen next to the 24" BenQ, and also get slightly more oompfh in terms of gfx power. Adding another 6950 would do the trick surely.

Currently the select few games that I play don't run smoothly at 1080p and adding another screen would stress the system more too.

I have a 6950 TwinF III running at 870/1350 and I've had it running games smoother with lots higher overclocks (50+ on core and memory) but I'd really prefer not to run it at crazy clocks and temperatures (+10C) all the time.

On these clocks the temps never go above 62C and the system itself keeps under 60C thanks to the Noctua 12 and case fan most likely.

I'd like to add another 6950 but something cheaper than a TwinF as it's also not that easy to find anymore.

Was thinking something like this instead: More ordinary 6950

But I have some concerns, mainly regarding my mobo and my PSU.

1. Cooling/Overheating: The PCI-E slots on the Gigabyte EX58-UD5(rev1) are so close together that the top card, which would be the TwinF, doesn't get any air at all. There's barely 2mm separating the cards from eachother when both slots are used. Tested this with my 9800GT in the machine at the same time. Temps went crazy.
My friend says it would be enough to put some piece of plastic or some folded paper to push the cards apart to have more room for intake air for the top card.
Would that really be enough?

2. Scotty, more power: I have a 650W Corsair from 2009, can't for the life of me remember which model and not at home right now, it cost 80e back then and has yellow labels, not a beast by any means.
Is that enough to power both? Rest of the rig is in the sig.

3. Clock differences: If I downclock the TwinF back to it's normal standard 850/1300, it'll still be loads different in clocks to the standard 800/1000(?).
Can that cause any issues whatsoever?

Thanks to any who bother reading all of this and replying.

 

[insejn]

I might just sell my 6950 and go with a Sapphire 7950 OC instead. Less hassle, no fear of PSU not being enough.

I just seem to remember from some years ago that Sapphire wasn't the best of brands. Are these TwinFrozr lookalikes as quiet?

 

[tommybhoy]

1. Top card will heat up with about 10c higher than the bottom one, you can install an Antec spot cool fan and point it at the top card to cool it down or custom bungee a 120cm fan to do the same job if temps are too hot.

2. Your 650w should do the job, others here have used 6950 CrossFire with a 650w psu.

3. Different clocks are not an issue in CrossFire.

You will have less hassles with the 7950 but it won't be as fast as the CrossFire setup(providing said game has a profile).

6950 CrossFire will generally give about oc'ed 7970/680 performance.

Sapphire assemble all AMD's reference cards, so basically they make the most cards out of all the AIB's.

 

[insejn]

Thanks tommybhoy!

I'll consider over the weekend, wouldn't get any order until Tue-Wed anyway right now.

 

[ViRuS2k]

You could always buy a spotcooler and stick a peice of carboard or something inbetween the cards to seperate them a little more and then point your spotcool in-between the cards, worked wonders for my 2x 6970s.