Solved Computer won't boot after new PSU install.

[carz95]

so I just installed a new PSU, but when I turn it on nothing happens. It just does nothing. All my cables are plugged in. The weirdest thing is when I flip my PSU off with the switch on my PSU the lights on my keyboard start to flash. Any ideas?

 

[oscer1]

Hi first i would double check that you have everything plugged in right. and make sure the voltage selector is at 110v setting.

 

[ICIT2LOL]

Hmm as Oscar says mate and just as a matter of interest that flashing happens when the RAM is not right on my main desktop (Asus board).

If you have a digital multimeter it would be good to check the volts especially the pin 8 (grey cable) on the 24 pin plug see this
Voltage Rails - Power Supply 101: A Reference Of Specifications because as you will see the PSU has it's own test circuitry that will not let the machine power up if things are wrong inside it.

 

[carz95]

Could bad ram also cause the pc to shut down?
Basically what happened was my pc randomly shut down one day
and would not turn on. We thought it was the PSU and replaced it.
Now it still won't turn on.

 

[oscer1]

It could be motherboard also. Check for bad caps. I would suggest you bench test the computer. Take everything out of case. On a non conductive surface put motherboard one stick of ram cooler and if your motherboard has on board graphic use that hook power supply then short out the power pins on motherboard to start computer. Do you get a screen? Here very good guide How to Bench Test, Build, and Troubleshoot Your Computer - Tech Support Forum

 

[ICIT2LOL]

Well mate you could have just got a dud PSU did you check the volts? I doubt very much if the RAM is bad as it has nothing to do with the machine starting it only comes into play after the system powers on and starts to load applications.

If the machine actually started the you could run a test for volts with HW Info. Just as a matter of curiosity what was wrong with the old PSU?