I use an Athlon64 X2 system, 4800+,
mainboard is an msi one, dont know the exact model number (not printed on the mainboard)
Geforce GT210 PCIE graphics card, onboard audio works,
onboard LAN did not, so I added a 3com 3c905.
Had to go into BIOS and change SATA mode to "AHCI" or the install failed
Hardware I have used before:
Pentium 4 on Intel Desktop Board mainboards(Have tried 3 or 4) have all worked,
a safe bet for wired networking is a Realtek RTL8139 PCI card,
safe bet for working audio is a SoundBlaster Live! 5.1 or Audigy2 ZS
For graphics, a decently recent NVIDIA card is preferred, from Geforce MX4000(2D only) GF6200(2D and 3D), up to GT210(2D and 3D) is what I have used with success.
VESA has worked on most cards I have tried, although a bit slower.
Oh, and a minimum of 1GB RAM if you intend to run OWB(the browser) IMHO.
2GB is plenty for all things AROS.
Its worth the time to build a dedicated AROS box, and most of the hardware can be had for free if you have hoarder friends like I do ;-)
Best of luck