Wanna help with video card upgrade?

Ok here are current specs:

Cooler Master Hyper N520 cpu cooler
q9400 2.5 ghz cpu
evga 9800 gt
XFX nForce 750i SLI Extreme Edition mobo
thermaltake v9 case
6gb ram ddr2
Ultra LSP750 750w Power Supply
vista 32bit (but i will change it to 64bit i just couldn't find my 64bit last time i installed os and i don't know if windows 7 works on mobo)

So i'm thinking of upgrading gpu and i am sick of dropped frame rates so i will go overkill. I was thinking gtx 460 in sli or something like that. my price limit is $400. First can my power supply handle 2 gtx 460s? and here are 2 gtx 460s i am debating between which is better?

then there is 20 off coupon with each

Oh and how much would these cards be bottlenecked and is it worth it?

the xfx 750i works with 64 bit Win7, that's what I'm running, and yes, one 460 has a tdp of 150w so two would be around 300w leaving roughly 400(due to efficiency imperfections) for the rest of your system.

that already goes over your $400 budget. I would suggest a single GTX 470, it runs all games great, wont run as hot as 2 GTX 460s, it will eat less power, and you wont have to put up with the occasional stuttering glitches caused by 2 GPUs. Just make sure your case is big enough

Why go sli when your cpu is a HEAVY bottleneck?

Not saying that it's bad, but it will defineatly bottleneck you.. youre fine off with a single gtx460

Also, I don't see how the motherboard wouldnt work on windows 7...