I have a desktop with an nVidia GT 9500 which has two DVI slots. I have a 24" TN-Panel TFT on that and it looks pretty good. Then I hooked it onto the DisplayPort of my ThinkPad with the Intel HD 3000 card with an DP->DVI adapter and I think that the fonts look even clearer.
Both computers run Kubuntu 12.04, although the ThinkPad is freshly set up, while the desktop is migrated from the previous release.
Is this a hardware thing or is it just some setting in the anti-aliasing or sub-pixel-hinting?