Is there something fundamentally wrong with AGP?

Well, I know the answer to the subject, of course...

But there has to be something fundamentally wrong
with my understanding of the AGP setup, BIOS
configuration to work with an AGP card, etc.

I have two different machines (one has an ASUS
A7V motherboard, one has a newer ASUS A7N8X, with
PCB rev. 2.0, or 2.01 I think), and on both I have
been unable to make any AGP card work fine.

I just bought a new AGP8X card (an XFX, with nVidia
GeForce chipset), replaced the PCI card that I have,
and the monitor receives no signal.

The motherboard does not beep funny, so it seems
to be recognizing that there is a video card
attached.

But I don't even get to see the first screen, in
text mode! (the green led on the monitor never
turns on -- the led that indicates that the monitor
is receiving video signal).

After putting back the old PCI card, I checked the
BIOS settings, and everything seems normal:

AGP8X: Enabled
AGP apertu 64M

And two other settings that I don't remember exactly
(sorry, can't see the BIOS and use my computer to
write this message simultaneously :-)), one of them
is "Enabled", the other one is "Auto detect", or
"Auto", or something along those lines.

Is there something else that I'm missing? I would
be very surprised that a brand new video card (in
a retail box) just happened to be defective, at the
same time that I'm not able to make the other AGP
card work on the other motherboard? Sounds to me
like the statistics speak for themselves...

Any help/ideas/advice will be appreciated.

Thanks,

Carlos
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