17th June 2002
Ther is very little difference between 4x and 8x. If you're one of those completely insane people who overclock every component and make their computer into a fire hazard the likes of which the fire brigade have nightmares about just to get an extra 1 frame per second in the latest game, then there is a difference. To normal people, the difference is minimal. Certainly not enough to warrant buying a new motherboard if you can't really afford it. And the difference between 8x and PCI-E isn't sufficient to waste so much money on either, not for a year or two at least.
Jedi871308x has almost double the bandwith through the bus than the 4X.....basically...faster transfer speeds from the card to the mobo
So... More Power to the Card, More Speed }>
Chances are if your rig has x4 AGP then it's a fairly out-dated system anyway. But like Matt says, unless your a Pyro there's not all that much difference.