I have XP Plus! and my Radeon works fine .. no problems at all .. these are the default drivers xp is using .. i havent even loaded the newer radeon drivers yet .. but no problems here

------------------
Asus A7V266, AMD 1100 ( C series), 72x Kenwood CD, 8x4x32 Hp 9100I, ATI Radeon AGP 4x, ATA 100 (7200 RPM) 30gig, ATA 100 (7200 RPM) 13gig, 392mb pc2100 DDR RAM, Sound Blaster Live X-Gamer, Netgear 100-TX NIC