To whom it may concern, upgrading an old Voodoo 3 to an ATI 9000 worked perfectly on my machine. Not a glitch in three weeks.
Configuration
unmodified BP6 2x 533 not OC'd,
384 cheap RAM
9.1 Gb of SCSI disk on 29160
40 Gb of IDE disk on HPT 366
AGP: Radeon 9000 Atlantis
PCI1: Creative SB Live platinum
PCI2: LAN card (DLink 530TX)
PCI3: Adaptec 29160
PCI4: IEEE 1394 adapter - unknown brand
OS: Windows XP pro