If it will, then try running a full system scan with a good antispyware program. If it won't restart in Safe Mode, then restart the computer, pressing the F8 key, once per second till it loads a selction screen. Use the up/down arrows to select "Last Known Good Configuration", then follow the prompts to restore the computer back to an earlier date.
In addition, make sure to use compressed air to blow out all the dust and junk from the fans, processor and heatsink, and the vents.. If it's a desktop computer, remove the cover and clean everything out good. While in there, look carefully for bulging capacitors on the motherboard.. If you find them bulging or leaking, you may need a new motherboard..
And yes, if you've got an extra power supply available, give it a try.
Hope this helps.
Grif

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