could be a power supply problem. the 115/220 is the voltage selector, leave it on 115 if you're in america or turn it to 220 if your in europe. if the cd rom drives are empty, then they are only going to light for a sec on bootup and thats it, put a disk in, does it spin and do whatever it's supposed to do? if it does, it's ok, if not, it's bad. but it could be the power supply. check to make sure that the connector from the power supply is securely fasened to the mother board. also, swap some of the power plugs around going from the power supply to the drives and see if the lack of power follows. you can use a power supply from another computer, as long as it has the same type of mother board connector ( if it's not he same, it won't fit, so if it fits, you can use it). i had a computer that wouldn't turn on and i had to fiddle with it to get the machine to boot up, turns out it was the power supply. cann one from an old computer or go buy a new one, either way, you should be good.
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