Sounds like either video setting or something using up system resources.
Check the refresh rate in your display settings, maybe the monitor doesn't like the present refresh rate, or the video card doesn't have the memory to keep up with it. Try updating video drivers, and check the video card manufacturer's website for any reference to a documented problem similar to yours. They might have a patch.
The "utility has my HD locked" needs to be explained a bit better, and what utility are you trying to run when you get this message?
For optimization, run scandisk from a DOS prompt. Boot to a Win 95/98 Start Up disk, or use the F8 key, and at the boot menu choose Command Prompt Only type this command line at the A:\> or C:\> prompt to run scandisk unattended:
scandisk all /autofix /nosummary /surface
This will run a full scandisk on all drives, and surface scan as well. Scandisk should be on the Start Up disk, or can be run from C:\> Prompt.
NOTE: Do not try to run scandisk from a DOS prompt withing Windows, boot into DOS to do it. Windows scandisk will work, but doing it from a DOS prompt also defrags the section of the drive where the Windows swapfile would be in use while windows is running, plus you can specify certain parameters that make life easier.
Then reboot into Windows, and run defrag. Turn off everything possible before running defrag, using the icons in the tool tray, or Ctrl + Alt + Del and End Task everything but :
Systray, Explorer, rundll, rundll32 and Rnaapp if it's running, everything else can go.
Check the System resources, something might be eating them up. If you don't have the Resource Meter in system tools, open Control Panel and add it, from Add/Remove Programs, and have the Windows CD handy.
How much is running in the background? Office programs' fast find feature is notorious for eating up resources. First thing I do when I have to reinstall my machine is delete the fast find icon from the Start Up folder. I drag everything else in the Start Up folder into a temporary folder I create somewhere, so it can be replaced easily if I decide I need it someday.
If you had everything...Where would you put it?
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