TR Forums

So, my desktop that I built, with the help of you folks, has a strange issue that's cropped up: It turns off with no fanfare.

It's only done so twice. But, once it has, it doesn't turn back on. I've unplugged and re-plugged all the cables. Nothing. Last time, I took it to GeekSquad (I have no spare parts to troubleshoot with) to do some diagnostic, but it turned on right away for them and then turned on right away for me when I got it home. Last night, it just shut off, and hasn't yet turned back on.

I did note the CPU heat sink was loose (I've tightened it again), but it should do a thermal shutdown and should have come back on, as I understand it, once it's cooled off with no more effort than my pushing the power button.

So, I'm thinking it may be the PSU that's to blame. How can I check that the PSU is the culprit?

Best way to test that is swap in a different PSU. If you don't have a spare, perhaps you know someone you can borrow one from?

I assume you've verified that power is good at the wall outlet?

Does *anything* happen when you push the power button when the system is in the bad state?

Things that can intermittently cause a system to shutdown and failure to reboot might include:

1) Loose cable connection (you did try that)
2) Bad USB, eSATA, or SATA peripheral (have you tried a minimalist configuration, different mouse and keyboard in different USB ports, etc.?)
3) Bad USB or eSATA connector with a pin occasionally shorting (tricky to diagnose, but a flashlight inspection of the ports might provide a clue)
4) Peripheral card not installing securely (have you checked for that?)
5) Motherboard standoff shorting intermittently due to poor mounting (have you checked for that?)
6) Bad motherboard or power supply

If you get to step 6, my approach would be to run the PC in a different location for a little while, just to make sure you don't have a weird power/grounding or cooling issue appearing at the normal location. After that, replace the PSU. If that solves it, assume the old one was defective and RMA it (if still under warranty), and make sure to describe the problem the way you did here, so they know it's intermittent. If that doesn't solve it, you might have a bad motherboard.

The PSU should still be under manufacturer warranty. By your system specs, even if you added a $500 GPU the 550W PSU shouldn't have been overloaded and your i3 can't be overclocked.

just brew it! wrote:

Best way to test that is swap in a different PSU. If you don't have a spare, perhaps you know someone you can borrow one from?

I assume you've verified that power is good at the wall outlet?

Does *anything* happen when you push the power button when the system is in the bad state?

No spare PSU.

We just had an electrician redo the wiring (yay old houses!). The outlet is now grounded and properly wired. Other things, like the monitor and laser printer are running just fine.

Nothing is happening (or happened) when I push(ed) the power button.

ludi wrote:

Things that can intermittently cause a system to shutdown and failure to reboot might include:

...lots of steps.

I haven't yet tried 2 through 6, except 4 because there are no cards for me to remove. I'll give it a go in a few hours.

titan wrote:

just brew it! wrote:

Best way to test that is swap in a different PSU. If you don't have a spare, perhaps you know someone you can borrow one from?

I assume you've verified that power is good at the wall outlet?

Does *anything* happen when you push the power button when the system is in the bad state?

No spare PSU.

Woohoo! I have a spare PSU!

Our IT consultant just so happened to have a machine destined for the dump that has a working PSU that's also happens to be recent enough to be compatible with the board.

Yay! My suspicions were correct. My PSU is dead.

I had pulled everything out, disconnected all of the cables except those that are strictly necessary for the case switch, motherboard, CPU, and HSF.

Nothing with my PSU. With the borrowed, cheapy 280W PSU, fired right up into the UEFI saying everything is just peachy.

Now to figure out how to RMA this thing....

So, the sending in the unit for an RMA was actually quite easy.

And, Seasonic is being fairly quick about it. They received it Thursday evening and are testing it now. I know this because Seasonic also gave me a link to a status page that I can track progress on the RMA.

They also had some troubleshooting info, which had really clear markings on a clear photo for the steps, for me to try as I was filling out the RMA.

Yes, it sucks a little that I had to pay to ship the PSU to them. But, it is a lot cheaper than buying another unit. I'm going to venture that they make me pay to ship it to them to cut down on frivolous RMAs for working units.

Seasonic still gets my seal of approval.