For setups like 1600x900 and lower would be great for gaming.At higher resolutions if the cards are 896 MB,they suck hard.
Worst setup I have in the last year was 3x275GTX 896MB cards.
Could not run the games I wanted too with high AA at 1920x1200 without being a stuttering mess.
Others will tell you there great at higher resolutions but for me it was terrible,only owned the cards for a couple hrs before I put them up for sale.