Isn't Amithlon a pain to get working? Well worth it in the end IMO...
Now, GFX cards:
You are quite correct, for hardware acceleration you really need a GF 4/5 card as the most 'modern' you can get away with (I forget with regard to Matrox & ATI).
So what's the problem?
PCI-Express I'm afraid...
...the kernel recognises a GFX chipset by the card's internal ID code which generally is different in a PCIe card when compared to the AGP/PCI version. Even though the chipset may be identical to a known-supported AGP/PCI version because of that 'unexpected' ID it's not recognised so all you get is VESA.
What can be done?
1) Updated kernel that supports more than a very few PCIe cards. (not likely)
2) Get a mobo with AGP/PCI rather than PCIe. (a bit of a pain that)
3) Trawl Amithlon.open / 'net for one of the very few PCIe cards that 'might just work'.
4) See about using one of those GFX BIOS-Hacking utils to change the card's code to the PCI/AGP equivalent. (doable but very risky & may stop the card working with other OS's)
5) Put up with VESA - Yes I know it's very much slower than accelerated but still very much faster than any 'real' Amiga RTG system.
Oh, um DVI:
DVI isn't 'safe' under Amithlon. If it works for you (probably using a newer kernel) that's a bonus but don't expect it to even when the docs say it ought to...
...I've even seen a fully supported card with DVI & VGA-out seemingly work fine with the DVI-out only to realise using the DVI has flipped Amithlon to VESA mode & slowed things down - weird, eh..?
And the lesson is?
-If you want an easy life build your Amithlon Box with Athlon-XP era components carefully following the compatibility docs.
-If you want a 'more modern' setup it can be done but what works & doesn't is in the lap of the Gods...
...searching the Amithlon.open group for suggestions is a good idea.
-Don't give up hope: A fellow EAB member tells me he's got Amithlon working on a setup that in ALL regards should NEVER work - but it does!