I stupidly installed the wrong memory module in my computer and turned it back on. A funny noise came out of the speakers, and the screen zapped out. Now only the fan and the power light come on. No hard drive activity at bootup or screen response. I replaced the memory module with a new (correct) one, replaced the motherboard, and still no change. What gives?
:rolleyes:

Replaced the motherboard and that changed nothing? Something needs to be re-thought here.
Please restate what happened, giving the model number and the bad memory as wells as the correct memory.
It sounds as if you have had a major cataclysmic event... strange, even for the mistake you made... A major short can damage everthing inside the case... and perhaps that happened.
But it would be unusual to have the motherboard replaced without any change
You need to test the hard drive in another machine to see if it is detected.
You should also test the power supply. If it was damaged, it could be sending errant power and readings to the other components.

Sounds like you bought a nice, expensive lesson in computer repair. Soon you will be as dangerous as the rest of us techs.

you mostlikely murdered your machine.
You should be trialed and put in jail :P

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