Green light on back of power supply is lit, but pc wont power up. m7250n desktop.

I'm sure you have tried most of these steps but I'm going to list them any way so we have a complete picture of the trouble shooting process.

The first step that should be taken is to verify that there are no lose or disconnected wires coming from or going to the computer. If when starting the PC your getting no power than there is an issue with the power supply. If you are getting power to the PC than you should listen for the beep code on start up. 1 beep after starting the computer signifys that the power on self test (Also known as the POST) has completed with out issue. When getting any other type of beep code you should research the meaning of the code. Beep codes differ from company to company. The best way to identify the meaning of a beep code is to type the manufacture, model and number of beeps into Google. Another possible issue is that your hard drive is corrupt. If this is the case than your computer will pass the power on self test(POST) but will have a message like MBR not found or one of many other errors. If you are getting an error than it is also a good idea to research the error to determine the proper fix. If the PC seems to boot correctly but there is no image on the screen than the issue may be a result of a bad video card. In that case the video card will need to be replaced.

I hope that information above has helped is some way.
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