Originally Posted by Beefdawg
Thanks for all the replies once again, now one more question....hows the whole overheating thing on the 1gig gigabyte with zalman fan version of the 4850? Because my 7900gs overheated a lot but i got a third party zalman cooler and it helps...but sometimes my card still overheats which causes artifacting. Just wondering if the card does well under strain?
To be honest, you shouldn't try an HD 4850 with a 375w dell psu. It wouldn't be a good choice.
Go with the HD 4670, it will be able to play Oblivion and Fallout 3 on high settings. And yes, it will be a big improvement over the 7900GS.
Get the 512mb version, like Red said before. The 4670 is also very easily overclockable, and when you overclock it, it can keep up with the 9600GT.