Even with the fastest computer, it will be a HUGE waste of money. Mining one bitcoin with just a PC now takes millions of years. You'll want a 1 TH/s or faster ASIC machine to start a small mining-at-home operation. -- so NO, never use a PC, no matter how much hardware you have.
You may buy miners here
https://www.ebay.com/sch/Miners/179171/i.html
But its not worth it.
I trade my bitcoin (and other values) on
https://www.etoro.com instead.