Re: Upgrade to gtx260 from 8800gt?
I'd stick with the 8800 for the time being to be honest.
ATI have released their DX11 cards and GF100 and derivatives of this will soon follow.
The GTX260 is an "old" card so you'd be buying basically obsolete hardware.
Plus your cpu is holding you back with better cards. Just replaced my 18 mth old GTX260 with a Radeon HD5850 (boo!) and had to flash the bios. This reset my Q6600 to 1.7ghtz and the cpu became a real bottleneck.
All my benchies and scores dropped by 50%. Found the problem was the cpu multiplier was set to 6x and reset the multiplier to 9x 300 fsb and hey presto all scores back to where they should be. It made me realise how much the cpu can hold back the gfx card.
I'd recommend keeping your card for at least another 6 months and then decide.
Also 1440x900 will not tax the card at all. With my new Radeon and the old GTX260 at 1680x1050 I am able to crank all the settings up to max and the cards cope admirably (except for Crysis of course!).
As one of the posters said you're better off buying a bigger monitor first.
My 2p's worth
Asus P5N32-E-SLI mobo, Intel Core 2 Quad 6600 at 2.7, Radeon HD5850 1GB, HP 22" LCD @ 1680x1050, 4Gb AData 800 mhtz ram, 1TB Samsung Spinpoint F1 & 250gb Seagate H/D, 2x DVD Burners, X-FI Xtreme Gamer, Thermaltake ToughPower 700w PSU