Dell PC XE2 freezes when using GPIB drivers

I started using new Dell PC 'Optiplex XE2' (using Windows 7 64 Bit) with GPIB 488.2 devices and GPIB drivers V3.1.2. It communicates OK for a few hours and then the PC freezes. Reproducible every time after a reboot. Tried the latest GPIB drivers (V14.0), no improvement.

The PC has worked OK for many months, when I didn't use the GPIB device.

Same hardware (PCI GPIB card) and driver version work ok on other Dell PCs (e.g. Optiplex 9010).

Any know issues? Workarounds?

Thanks in advance

Ajit