So, I am on my computer with my cell phone on charge laying on the top of my case. All of a sudden, my computer turns off, moments later, I receive a text message.

Could my cell phone interfere with my power supply (or other component) to cause a failure?

No.

Probably not. I'm thinking it was a grand coincidence.

No. Your power supply is inside at least 2 conductive layers that reduce the destructive power of radio waves, EMP, and cats.

Well, on the issue of power supplies...

My system has gotten into the habit of turning off.
I'm pretty sure it has to do with my power supply because when the computer turns off, nothing else does.

The current one is a POS 400W one that came from Gateway, but I just don't want to have to mess with all those damn wires.
So, do I have to buy a new one?

That Sparkle unit isn't really a bad power supply, but it's hardly a great one either. Lower-middle of the line, it would do fine if it was working properly. However, given its age there is a good chance it has bad capacitors which are causing your power off issues.

Get a replacement from a reliable brand. You almost certainly do not need another 400 W unit unless you have a really high end video card. A good quality 300 W or so is much better than a crappy 400+ W unit. Then again, the price difference is minimal, so if you find a good quality 400 W for a decent price you aren't going to hurt anything except a tiny bit of efficiency.

Changing a PS is easy, it's really just a few wires that only plug in one way.

Ok.
So, I picked up an Antec 500W power supply yesterday and installed it.
It worked fine all last night, but a second ago, less than 12 hours after installing it, I'm playing WoW and it just shuts off. Same thing that was happening with my old one.

Check your motherboard for bad caps. See if any of them look like small leaking batteries, or a bulging at all, especially at the top.

Have you always been gaming when your PC shut off or something similarly CPU intensive? Could be overheating. Is your heatsink and fan clean and good enough?

That Antec you picked up is new right?

Overheating is a probably cause. What about your incoming power- Do you have a power conditioner? Not just a surge protector but a UPS of some type? Its possible you could be getting power spikes that are causing the power off issue.

Well, I let my CPU run at 100% for 2 hours. The temp never broke 60C, and my computer was still on.

I do have it hooked up to a power strip with my printer, monitor, and phone.
But, there was a definite problem with my old power supply as the last night I used it, it started making a buzzing sound that faded in and out.

Well, I have narrowed it down to my GPU overheating, as when I play games with the side of my case off, it's fine.

Is there anything I can do about this?
I'm considering a PCI case cooler.

Posted by tholcomb Is there anything I can do about this? I'm considering a PCI case cooler.

Make sure there is adequate air flow through the case and that you have inlet and outlet fans. Make sure all heat sinks and fans are clean and free of dirt/dust/etc. Also- make sure all fans are operating correctly.

On the extreme end you could switch over to liquid cooling...





edit- added some more suggestions

Posted by tholcomb Well, I have narrowed it down to my GPU overheating, as when I play games with the side of my case off, it's fine. Is there anything I can do about this? I'm considering a PCI case cooler.

Does your case have an intake fan that blows onto the GPU plus proper outlet fans? Make sure you have enough airflow.

Rogers phones tend to interfere quite a bit with audio products.... its possible that with bad caps and phone interference... the issue could be made worse as long as there is data going to your phone. If the caps werent weak, likely wouldnt interfere as much

A year and a half later, I think I have this figured out.

It's my MCP. Comp turned off while I was playing Fallout, I turned it back on and my Everest widget said my MCP was at 214F. I'm pretty sure that's too hot, but I could be wrong.

I used to have the same problem. For weeks I would be frustrated at my computer constantly restarting while gaming.

Solution: Move the power bar away from feet.

Yes it can.

Example, the Samsung Notes have a magnate in them that will activate various accessories. Also, some computers have a sensor to tell when the lid is shut, put these together and the computer will think you want to to shut off.

I have seen it happen, and it took my buddy a while to figure out why his computer randomly shut down.