Whats is the best AGP card for gaming?

I currently own an HD 2600XT. But ever since the first day i got it ive had problems with artifacts on the screen and the only to solve this is by underclocking the card to 790 core and 690 mem when it runs 800 C and 700 M. I need a new card, am i not looking for the X1950 as those are very old. I hear the 3850 and the 4670 i think may be...but i would like an experts opinion. Thank you in advance.