After my computer goes to sleep, I can't get the monitor to wake up again about 80% of the time. I just have to do a hard reset.

I can connect via remote desktop without any problem.

I have tried pressing keys on the keyboard and moving the mouse to no avail. If I turn the screen off and on, it just says 'entering power saving mode'.

Configuration:

OPTIPLEX 960 MT - Bios version 3
256MB ATI Radeon 3470 PCIe
2408WFP
DisplayPort

I tend to think that it is DisplayPort related. I never had this issue before using other computer-monitor combinations and DVI.

I tried installing the newest BIOS on the computer and installing the newest ATI driver. No change.

Any ideas?