If you go back to factory conditions, it will be as fast (or slow, depending on what you expect) as it was when it was new in 2011.
If that's not fast enough, better buy a new PC then trying to upgrade this with a new PSU, motherboard, CPU and RAM.
Computer is a very slow computer. Can the mother board cause it to go slow? This is a cheap pc and has a very cheap mother board.

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