That's a sure fire way to go back to when it worked.
If it doesn't work there your PC has hardware issues. Laptops often are neglected for maintenance. The most common problem I see is dust and lint in the heatsinks that eat performance. Your new to this owner will often claim it's not heat too.
I have a trash HP netbook with a 1.7ghz i3, 8gb ram and Intel Family HD intergrated graphics, which I have owned for 3 years. Recently whilst running games my fps has dropped from it's previous 40-50 to 20-25. I have checked task manager whilst running the game and neither cpu nor memory seem to want to go higher than 65%. However, when running multiple heavy applications at once it can run at higher percentages. I have done a windows memory diagnostic check, malwarebytes root kit, avasts free antivirus (full) scan and do memory cleaning often. All of these have yielded nothing. Any ideas as to what the problem may be?

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