I would do that because it will clear any overclock and then redownload the drivers for the graphics card.
I built my own gaming pc a couple years ago. The specs are i7 6700k, msi gtx 1070, 16 g of ram, asus z170 motherboard, and I run windows on an ssd. I have had it overclocked but it was not performing right so I tried to unoverclock it which only made it run even worse. I tried to reoverclock it to see if it would perform like it did before but it is still performing horribly. Windows is lagging and im only getting 30fps in most games.

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