Evo,. .thanks for that. I'll try a PCI graphics card (I have an old Matrox G100 around somewhere). The CPU was made in about July 2001 (just before the Athlon XP came on line), so hopefully that bug shouldn't be present - but I may well ask AMD for their thoughts.. .I've heard elsewhere that the VIA/Athlon T'bird/Win98SE combination is beset with problems, so I may try Win XP to see if things improve.