I'm running an Iwill XP333-R with an R9700 and MBM5 just fine. Sure, MBM's voltages are off, but the temps are accurate. I don't have the text corruption your friend is having though. I would definitely try the 6159 (leaked) drivers as a fix. The 3dmk1 score seems low, but the XP333-R needs a high FSB to get really good 3dmk1 scores. I get 13k with my MP 1900 at 9.5x180FSB. The more impressive number is getting 9k with 4xfsaa and 16xaf enabled at 10x166 fsb...
Mize
Current Rig:
DFI LanPartyUT RDX200 CF-DR -- 11/02/05 BIOS
Athlon64 4400+ X2 Toledo -- x1800-xtpe -- Both Cooled by Zalman Reserator 2
2x1GB OCZ PC3200 Plt-EL (OCZ4002048ELDCPE-K)
300GB Maxtor MaXLine III 7L300S0 SATA150 HD -- 320GB Seagate Barracuda 7200.10 HD -- Lite-On SOHW-1693S DVD+R
OCZ Powerstream 520w power supply -- On-board Audio -- Windows XPPSP2