My motherboard manual (Asus A7V8X-X) reads: "Only install 1.5VAGP cards on this motherboard to prevent damage to your AGP card or motherboard." Am I right in thinking that as long as the card fits physically - i.e., has the right physical configuration in terms of slots and notches - it is the right kind of card? The card I have, and which I think has been giving my motherboard some problems in terms of adequate power, is the Atlantis Radeon 9000 PRO, and it makes no mention in its list of specifications (http://www.sapphiretech.com/vga/9000pro.asp) whether it is a "1.5VAGP" card or not.

The subject line, incidentally, should read: "What is 1.5VAGP"? It seems like it didn't like the quotes.... !

Some AGP info here: AGP info

Well, thanks for that - but now I'm afraid I'm even more confused. The first chart seems to suggest that a m/b that specifies 1.5VAGP - like mine - can only run 4x, 2x, or 1x AGP. But my board also describes itself as "x8 AGP". Am I being slow, or is this a contradiction?!

... and another thing. Does the name of my card - "Sapphire Radeon Atlantis 9000 Pro" - mean that it is an "AGP Pro" card? If so, does that mean that it won't work in an ordinary AGP slot, as this site seems to suggest? If so, that might explain things. Incidentally, the problems I've been getting have been that the power supply makes an excessive groaning noise on booting up when the card is installed, with the subsequent failure of PCI ethernet cards... Don't know if that sounds familiar to anyone.

The pro part of the card name just means its good, as in better than a non-pro. Vid card compatibility goes like this: Each version of the AGP Spec covers two levels of bandwidth. So agp1.0 = agp1x/2x, agp2.0 = agp2x/4x, agp 3.0 = agp4x/8x. Each mobo is compatible with a vid card that is one agp spec number away. agp3.0 works with agp2.0 and agp3.0, agp2.0 works with agp2.0 and agp1.0, etc. So the result is: the only thing to avoid is using an agp2x vid card on an agp8x mobo, or an agp8x vid card on an agp2x mobo. Which means you will be fine. And some vid cards are "universal agp" which means they work with everything.

I have your motherboard. Well, I have mine, but same as yours. I run Radeon 9000 pro (Sapphire Atlantis). It works. Your motherboard is designed not to even SHOW the 8x option in the bios unless there is an 8x card in the slot. Clever eh? See ya. (ps same goes for 400mhz ram, if it ain't installed, it won't show you an option to select it's speed).