Screens freeze, color changes, requires cold start and Startup repair

4 year old HP desktop, Win7 SP1, 4g ram. quad Intel, Nvidia GeForce 8600 GS. Several days now requiring multiple restarts with all OK for awhile, then freezup and won't shut down and requires power button shutdown and then the Startup Repair done each time. Have run Malware Bytes two or three times, Security Essentials twice, Startup repair several times, MS Defender offline scan once. System Restore several times as well as the "Last best", and all eventually worked for awhile. Made new restore points after good session. No bad stuff, virus, trojan, etc. found. Scannow several times with nothing shown. Startup Repair log a few minutes ago showed "Root cause found" "Unspecified changes to system configuration might have caused the problem" "Number of root causes: 1". Using dual monitors and when freeze occurs right screen background of open window turned pink, and left screen developed large darker blue swirls in the background. Hope this means something to one of you. Suggestions appreciated. Roving

Please post back a screenshot of your maximized Disk Management drive map and listings:

1. Type Disk Management in Start Search box.
2. Open Disk Mgmt. window and maximize it.
3. Type Snipping Tool in Start Search box.
4. Open Snipping Tool, choose Rectangular Snip, draw a box around full map and all listings.
5, Save Snip, attach using paper clip in Reply Box.

Tell us what is on each partition.

Try updating your Display driver.

Work through these Troubleshooting Steps for Windows 7.

I'm still working my way through the fixes and no joy yet. Takes lots of time as half of the time I get "Pink screeened" and then have to work my way back from restarts to get back to the fixes. At the moment I have all services stopped except Security Essentials. RPC Endpoint Mapper and Task Scheduler just keep re-appearing. Nothing else does, so I guess no outside source is messing with me. The pink, and sometimes the blue swirls appear after it is on awhile and I move the mouse to click something on the window. It seizes up at that point. Thanks for your interest.

I'd want to run SFC if necessary from DVD/Repair CD, change out Display driver to newer or another recent which stablizes visuals, troubleshoot repeat errors in logs especially at time of probs, check for Solutions.

If these fail I'd run a Repair Install which essentially reinstalls the OS while keeping everything in place. However the possibility that another program or setting is causing the problem remains, so you may want to take the exciting opportunity to do a Clean Reinstall that's better then getting a new computer !

Many thanks for the help. Chasing stuff that kept changing just wore me down and took more time than it was worth. Late yesterday I did a reinstall of Win 7 using the SP1 iso following Brink's instructions and it went perfectly and I am up and running and the problems have disappeared, at least at this point, and hopefully for good. Thanks for the help and interest.