Probably a dumb question but I currently have an older G80 based 8800GTS 640. It works great for most games but it chokes on Crysis at 1920 x 1200. I could add another G80 based 8800GTS in SLI mode for $129. Would this setup come anywhere near the performance of a GTX 280?

Thanks for any help in advance.

Do you have an SLI capable MB and a big enough PSU to handle-it?

I just upgraded from sli'd 8800 GTX's to sli'd GTX 260's, and can now run Crysis on high at 1920 x 1200. Previously topped out at 1600x1080, or 1400 x xxxx if I wanted everything butter smooth.

You should be pretty close to the 280 with your setup by adding another card. Assuming you have a sli capable mobo, it would be a cheap way to vastly improve your framerates.

As said above, as long as you have an SLI motherboard and a capable PSU, it would be a cheap way to get decent frames at that res. The single GTX 280 will still perform better at that resolution though. At 1920x1200 on high, I average about 30FPS with my dual 8800 640 setup.

I've got an Asus P5N32-E SLI mobo and a corsair 750 watt power supply.

Go for the second card!

I think the 2nd card would be by far the best investment since you setup supports it. Crysis scales very well with SLI and you will probably get very similar results for a ridiculous amount of money.

Yeah, you should just SLi that 8800GTS then. If it was the 320, I would say no, but the 640 should be fine. You might get lower minimum frame rates than just going with a single 280, but it should still be a pretty good increase. Looking at the charts though a single 8800GTS 640 only gets like 17fps at 1920x1200, 0xAA, 0xAF, High Quality. I think if you SLi your cards you should be around 28fps with no AA and no AF at 1920x1200 on High quality. If you want to run Very High, then you're probably going to have to buy two 280s at the least.

Strange; I run very high everything with Af and 4xAA at 1680x1050 and it runs fine- average of 40-45 fps. I have 2 9800GT's- they must just scale well!

SLI is the way to go for you.

The G80 chips are slower than the G92 chips. Also he wants to run it at a higher resolution.

Thanks for all of the input. I decided to take the majority opinion and installed a second 8800GTS 640 (G80) in sli mode. My FPS doubled from 20 to 40 at 1920 x 1200.
I'm happy with the results and saved $300 !

Thanks again

yeah go for the second card. Cheap upgrade with better performance.