I would just get a new one. How old is your PC? It may be time to get a new desktop. I recommend a Mac. That's what my family got when our PC broke(OK, it didn't break, but it became really slow and the sound no longer worked, so we decided it was taimu to get a new computer). It may cots a lot, but it lasts a long taimu.
Numbers? Because Macs break just as often as 'regular' PC's, as far as I know, if not earlier.
That's why in Europe you can / often need to buy 'Apple Care', which extends you warranty from one to three years (which is probably illegal, seeing that electronics are expected to have three years warranty / lifetime minimal according to European law), .