Any reason not to go SLi with 7900gts?

[man_from_uncle]

I am a bit of an upgrade fanatic at the moment (as I know a lot of you are too) and even though I can (and probably will) do the next volt mod on my current card I know that i'll get an extra 5-10% out of it tops. Getting a second card though should give me power way beyond any single card and if I do the volt mod to the second card too I should be able to rival any dual card set up.

Obviously i'll have to think about cooling for the second card as well and if I use the vf900 this will put the case temperature up. Does anyone know what impact that'll have? I've been sort of tempted by 7900gt512 just because I think the heat sink has an exhaust and that might let me overclock further than a combination of 2 vf900s. Maybe some sort of

Has anyone got any thoughts? What sort of bottleneck will be CPU be? I might get a 165 or a 170 and hopefully get to FX-60 speeds or so. Any game other than Oblivion going to need more CPU power than that to let 2 7900gts shine?

 

[man_from_uncle]

Thanks for the responsies. I'm gaming at 1600x1200 at the moment, but this might go up if I can get hold of a 22'' crt monitor from work (though i'm not entirely sure I know what the max res on that will be.)

I only have the 256 meg card at the moment and I know that the the 512 version would be wasted in every way but the exhaust fan, and even then a vf900 might be a better bet. It's going to be pretty warm though if i volt mod both cards and don't expel some more air. Sadly the Asus premium i have has the pci-e slots at top and i can't put an extra exhaust fan above them and I suspect that even a powerful exhaust at the bottom of the case will be wasted (what with hot air rising and all).

 

[man_from_uncle]

Out of interest wellibob, I saw your 3mark06 score and it was pretty much blazing compared to mine. What settings did you use to get that high?

 

[man_from_uncle]

What about the CPU? I noticed your score was something like 1400+ which I'd have thought was beyond a single core....at least at 2.7ghz (as in your sig). Mine gets 1100 or so at 2.75ghz and my ram is pretty tight. You graphics marks though were pretty similar to mine and I think the difference in overall score was more to do with your processor.

EDIT: I also notice your 3dmark05 score was actually lower than mine, so it must be a difference in CPU settings as 06 is very CPU sensative.