What cards will my 4x AGP slot run?

My motherboard has an AGP4x slot in it, and I'm looking to get either a radeon 9800 pro, or a radeon 9600xt. On the boxes (respectively) they say 4x/8x, and 8x. What do those numbers mean? I mean, I got the impression that 8x is "better" than 4x, but that doesn't tell me how it's better or why. Someone please educate me! Also, will a card that only says '8x' work in my 4x agp slot? Thanks

 

The 8x AGP slot has a bandwidth that is twice as much as a 4x slot. However, 8x doesn't give you as huge of an increase in performance as it shows on paper since most applications can't use the full bandwidth of 8x speed anyway. Oh, and you can run pretty much any card in there. I think all 8x cards are backwards compatible with at least 4x.

 

my m/board only supports 4x and i ran asus ati 9600xt\tvd with no problems.

 

Correct. Ive got an AGP 8x card which I used in a 4x slot and it worked fine.