HELP!: i8600 with 9600PT... jaggy/ pixelated in-game graphics

Hi. Have a problem with my i8600. Games seem to run fine on it (KOTOR, Jedi Academy, GTA:VC) as far as framerates are concerned...... but the graphics seem pixelated in game. Or at least that's the best I can explain it. When I compare it to my old i8500 w/ 4200go it looks more rough around the edges. This is despite changing the card graphics options up to 8X AA, 16X AF, etc, and the game options... no matter how high or low the settings are it doesn't seem to look as good as the old 4200go.
I have tried both the stock Dell drivers and modded Catalysts to no real effect. Is this just part and parcel of the card? Is there a setting I'm missing in the drivers because I'm not as familiar with them as Nvidia ones (like the texture sharpening option on my old 44.03 drivers)? Or does this indicate a bad card?
BTW, I should add that this doesn't look anything like a heat caused problem (the card doesn't go much over 80 deg C from my observations (fanGUI)). It just looks pixeated as if it is on lower resolutions or graphics settings than it is...... and issue is only solved when going to insanely high resolutions (1680 x 1050 in GTA:VC).
Everything else about it seems fine, there are no heat distortions in games and it scores as it should in 3dMark01 and 03... so I'm stumped. Thanks.

Yeah, I tried them...... Its just arounf the edges and if you see like, a person, from far away in KOTOR for example, they look a bit pixelated. So I don't know... Any help would be good. I am undecided whether this is just part and parcel of an ATI card or if its defective in some way.... although I have never known a card to be defective in this way

KOTOR: usually on 1024 x 768, recently updated to v1.02 to see if that helped (offered 1280 x 1024), tried that out, and while it helped out a bit, it is still noticable and of course the framerate took a hit.
Most other games also only on 1024 x 768, like they ran on the i8500... as I said, they look more pixely than they did with the 4200go, and one of the main reasons I got this system was to beef up the graphics and framrates of my games... so you can understand why I'm a little stressed.