Hey Skurj,
Prior to my X45 purchase, I have been using a Cyborg 3D USB Gold and XP for a while now. No problems to report.
It shouldn't be, but probably is the number of USB devices. Might be sucking to much juice for all devices to be initializing properly. Recently, I had to replace a PSU to do any decent overclocking of my XP/Iwill XP33 rig. Turns out the 300W PSU I was using wasn't putting out like it should. Low 5V, 3.3V and 12V rails. Popped in a 400W Antec, tweaked the pots and now Im running an Athlon XP 1600+ at 1400Mhz, its stock speed, but at 175Mhz FSB. So, just goes to show a good PSU really is important for over all system stability.
Peace,
Yams