I have a 720p, HD projector that I play most of my games on using my xbox 360. I'd like to build a little gaming machine, but I'm wondering if graphics cards & drivers support the native resolution of my projector (1280x720). I feel pretty silly asking this, but I am not entirely sure of the answer. The last video card I bought was the ATI 9800 pro... and HDTVs were not nearly as prevalent.
Yeah pretty much any card you are looking at now a days will easily support that resolution in gaming. Hell even your old 9800 Pro does. One thing I have noticed is that for some HDTVs, overscan is an issue with Nvidia cards. This can be corrected by using "resize my desktop", but that just sets in a custom resolution.
I had to sell my 8800GT because of it, and went with a 3850 which allowed me to keep the 1280x720 resolution. Plus, it has Native HDMI which is great. Keep in mind that not all people suffer from this issue, a good friend of mine has no issues with his 8800GT on his TV, but my other friend had the same issue I did.