Here's some info on graphic card support based on kernel 4 (2.4.37.9).
There are a limited number of supported graphics cards for Amithlon. NVidia, Matrox, ATI and even Voodoo. Some better than others, though it still revolves around older linux 2.4 framebuffer support. Going through the kernel and gathering what we can find, this is the support breakdown for acceleration with each card type. This is information based on kernel 4.
Acceleration options defined in the kernel: (1)FILL_RECT (2)COPY_RECT (3)BLIT_TEMP (4)COPY_RECT_COMPLETE (5)DRAW_LINE
We can definitely see that overall nVidia has the most enabled acceleration functions with the Matrox and Radeon cards each dropping a different function. The Voodoo is the least supported and would be close to standard VESA framebuffer. I’ve not had a functioning PCI Radeon card, I believe AGP cards are the ones that work in Amithlon (based off a few laptops with AGP Radeon cards known to work). Matrox has both PCI and PCIe cards that work and nVidia has both AGP and PCI cards working. I have no feedback from anyone using a Voodoo card with Amithlon.
Voodoo cards are poorly supported though a nice Amithlon system can use Wazp3D quite well.