You might search for some kind of driver cleaner utility to wipe clean the drivers that came with the peds AND the current drivers you installed. Then reinstall the latest Saitek drivers and see if that cures your ills. I'm still suspicious of the power issue...i.e. the voltage being supplied to your USB port.
I built the system he has a 700watt PSU
Here is his build list
Case Thermaltake V9
Motherboard ASUS Striker II Formula
CPU Intel E8400 3.0 1333
Heatsink & Fan OCZ Vendetta 2
Memory OCZ 1066MHz DDR2 CL 5-6-6-18
Video Card EVGA 9800GTX+
Hard Drive Western Digital 640GB SATA II
DVD Samsung S223
Power Supply Coolmax 700 watt 109.5 amps across the rails