I wonder if anyone has had luck (or other experience) using a USB adapter in the PCI-X expansion bus in a Dell (2650)server?

In principle, this bus has tremendous throughput capability and is backward-compatible with 3.3 v PCI2.x cards.

But the two cards (480 Mb) that I have tried just stumble along and will not work with the URI fobs.  Mouse and keyboard work OK.

Is it possible that this being a 64 bit slot somehow confuses the USB driver?

Ken