If the system is locking up unattended, then there is a good chance the system is running a screen saver &/or power management.

Do not set virtual memory above recommended size, It will not help.

Have you disabled power managment for the monitor, & set the screen saver to BLANK?

If you do this & the problem goes away, try updating the video drivers.

I had the same exact problem with my new 8300 ystem.  Everything would be working fine until I let the system sit for an extended period of time.  The monitor would shut down (as was set up in power management) and come back on when the keyboard or mouse was used, but nothing on the desktop would work.  Shortcuts wouldn't run, right clicking the desktop didn't open a window and nothing on the START MENU would run.  Only turning off/on helped.   I ran Windows Update and it seemed to fix the hanging problem, but now the monitor won't power down.  The screen saver kicks on (nothing fancy, just Window's Beziers), but won't power down at the specified time.  All the power management options are set correctly and I don't suspend or hibernate, but I'd like the monitor to switch off after 45 minutes of non-use (the monitor is energy-star compliant and powered down properly before).

Any one else have any similar experience or successes?

k11, I'd suggest the Windows Update...it fixed the hang problem, but gave me another!!!

Thanks in advance for any advice!

K11,

Go to Microsoft`s Support Site and searh for your question, you`ll find your answers there.

Cheers,

T-B

Just a follow-up....the locking up issue hasn't happened since the Windows Update was performed and with the help of Microsoft support, it was found that some 3rd party application (I can only assume spyware or adware) was messing up the monitor shut-off feature.  After disabling everything but Microsoft apps in MSCONFIG, the system seems fine again. 

Can anybody recommend any good Spyware/Adware search and destroy software????

Thanks

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