You can start by killing off any ATI second and third generation cards (9x00, Xx00 cards) and any
Nvidia 6th generation cards
along witht he
7800's But if you look yuo said they they have been replaced with the 78xx which is a ? you mean 7900? And I dont think the 6 series hasnt been replaced with the 6x00, they have been replacd with the 76xx , as they have been replaced. (
6x00, 78xx)
There are only three card groups you should be looking at for both ATI and Nvidia:
ATI:
X1300 - X1300, X1300PRO,
X1600 - X1600PRO, X1600XT
X1900 - X1900GT, X1900XT, X1900XTX
Nvidia:
7300 - 7300LE, 7300, 7300GS, 7300GT
7600 - 7600GS, 7600GT
7900 - 7900GT, 7900GTX, 7950GTX