So I put together my new computer and it was working fine. I installed Windows 7 and installed my video drivers, but afterward I had no video. My computer wouldn't turn off so I tried turning my surge protector on and off. Now my computer will not turn on at all. I have checked everything and it is all connected properly. I have a gigabyte 790xta-ud4, an xfx 5770 video card, and an xfx 650w power supply. Any ideas? Is something wrong with my power supply?
Wow - the same thing happened to me just tonight. Just finished putting my computer together - POST'd first attempt, installed Windows 7 upgrade the first time then started installing it the 2nd time (the double install trick to getting the upgrade version to work on a new computer) and it shut off when it asked me if I wanted to download updates or something, and when I turned it back on it shut off in 3 seconds or so, and now it won't turn on at all. >.< So frustrating - I thought I was in the clear...guess not.
The best way is to borrow a known good PSU. If you cannot do that, borrow a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.
The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.
This checks the PSU under no load conditions, so it is not completely reliable. But if
it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.
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June 20, 2010 2:06:47 PM
So after some fooling around last night, I managed to jump start the computer by using a paperclip on the motherboard without the graphics card plugged in. Only problem is my motherboard has no integrated video so this is pretty much completely useless. I tried taking the battery out to reset the bios, but no luck starting with the graphics card. Does this mean the graphics card is defective? Or maybe some part of the motherboard? I don't have any graphics cards or motherboards lying around to test it out with so I have no idea which it would be.