Question Lenovo pre-built for mom, post issues. Why would a system not post?

[thesupremecourt]

I snagged what I thought was a great deal for my mom: a $150 pc with i5 3470, 8 gb ram, 500 gb hdd. It was really fast and worked well for about half of a year, but then it stopped working. There would be no motherboard beeps unless I took the ram out. I just purchased a new motherboard and it came today. I installed all of the components correctly, and as soon as I turned the computer on, it beeped just as before. Oddly enough, the computer would usually power on as soon as the cable was plugged, obviously some issue with the motherboard, and the new motherboard didn't do that. It still failed to post. Is there an issue with the memory? I bought a new stick of ram too, and apparently that failed to work as well.
Thanks Tom's hardware!

 

[Eximo]

Power supply usually goes in them. Make sure 12V, 5V, and 3,3V are coming out of it. Beeps would suggest that 12V was working enough to get the CPU mad about not having memory.

Dead CPUs can happen, but pretty rare. since you moved it between motherboards, check to make sure the CPU was properly installed. Check the motherboard for any potentially damaged pins in the socket.

Other than that, try the no POST guide.

"No POST", "system won't boot", and "no video output" troubleshooting checklist

"No POST", "system won't boot", and "no video output" troubleshooting checklist This checklist is a compilation of troubleshooting ideas from many forum members. It's very important to actually perform every step in the checklist if you want to effectively troubleshoot your problem. 1.Did you...

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