The USB 2.0 card was present during the Mac's month-long existence as a 533MHz machine, with no untoward behaviour evident. But your thought had also crossed my mind as an avenue of investigation, albeit a reluctant one. I have keyboard and USB soundcard in the built-in USB 1.1 ports, but printer and various comers-and-goers are attached at the USB card. USB for the hub in the ADC display (which is my obligatory alternative for the thumb drive since the DA itself is under my desk) is through the ADC port on the Radeon 7500.

Macally's USB2EHCI_v3_1_2.sit software did not make any difference, but neither did it cause the interference with the Apple USB2 .kext (so far) in 10.4.11 that Macally warns about. I believe that the USB2 PCI-X card is supposed to be plug-and-play with Apple's .kext, anyway, but at the next opening of the DA I shall remove it and see what transpires.

de