When using RDP to access my office machines (via VPN), I have a severe screen repainting latency. However, If I reboot the office machines, the latency does not re-appear., until the next time it is rebooted.

If left locked overnight (user logged on), it is fine the next morning.
If the office machine is forcably rebooted the issue reappears Once I RPD in again, and reboot the office machines, the issue is resolved.

XP Professional SP2
Work around: machine must be rebooted 2X

Any help is appreciated