1280x1024 to 1920x1080- how much of an FPS decrease should I expect?

Depends on the video card and the game.

See following reviews as an example:


Contemporary Graphics Cards in StarCraft II: Wings of Liberty
http://www.xbitlabs.com/articles/video/display/starcraf...


Contemporary Graphics Cards in Metro 2033
http://www.xbitlabs.com/articles/video/display/metro-20...


Contemporary Graphics Cards Performance in Battlefield: Bad Company 2
http://www.xbitlabs.com/articles/video/display/battlefi...


Contemporary Graphics Accelerators in Mass Effect 2
http://www.xbitlabs.com/articles/video/display/mass-eff...

Depends entirely on your system dude. I will say this, going from 1680x1050 to 1920x1080 I had a noticeable difference on my system.

My system:
q6600 @3.0ghz
4 gig ddr2 800
Nvidia GTX 260 216 core OC

One thing I will tell you for sure.. You will want a graphics card with at least 768, preferably 1gig of ram onboard. 1920x1080 is kinda the turning point - I would say 1920x1080 and above, you really want a 1 gig memory graphics card.

Screens 1920 x 1080 and above can really utilize more ram on a graphics card. I would say that your 1280 x 1024 would be fine with a 512 ram card..