"104" refers to the capacity of 100nF. No idea what "522" is supposed to mean. I know such odd numbers from SMD caps only. Could be 5% tolerance and 22V however, as these would fit in with common specs of such caps.
LewisRaz wrote on 2020-04-05, 13:10:
If its from a PC just make sure its higher than 12v and it will be fine.
No, since you can have a voltage of up to 24V on a PC (between -12V and +12V), and this is indeed not uncommon in certain circuits. Also, the next higher voltage for a cap would be 16V and that is *not* suitable for a 12V rail. So to be on the absolute safe side, you would have to use a cap rated for 35V.