Good point on the GPU. Perhaps not so much when only playing FSX since high resolutions mainly eat up VRAM and should work fine with the GPU powers. But if you would like to play modern shooters with 60fps or so, the GTX580 might struggle with the native resolution of the screen. So, for those cases, a GPU upgrade may indeed be a good idea for a Battlefield3 player or the latest Crysis and things. As said, FSX itself might be ok with the GPU of yours, although one would have to check if the 1.5gb VRAM or your card are sufficient at 2560x1600. Later cards come with 2, 4 or even 6gb, so that's a bit of a buffer.