Help please. Computer reboots on it's own?

[12Footer]

My wife's machine (PC) reboots without prompt, right in the middle of whatever. It's like it lost power. I tried to MAKE it do it, by slapping upside the box, jiggling the power cord, ect. It is also plugged into a UPS.
Virus protection (Norton) is up to date, but Could this be a virus? Any hints on where to troubleshoot?

 

[QC]

Re: Help please. Computer reboots on it's own?

My kids' HP used to do that and I found info on their site. Do a search on the Product Support page, if I recall, I was able to fix it. I think you may also be able to fix it with the Restore feature in XP and 2000 etc.

 

[i386]

Re: Help please. Computer reboots on it's own?

Most likely cause is bad power supply or motherboard.

It takes some testing and troubleshooting to track it down.


Here's what I ran into just a few weeks ago...
My customer had a dell computer. It was one of the tiny ones. Hers would just shut off or reboot itself randomly. I took it into the shop and first checked out Windows. There were no signs of virus or spyware. It looked like she actually used the computer to do work on. Next I ran a memory diagnostic (Mem86). No errors. Next I ran chkdsk on the hard drive. No errors. Since it was a slim line computer, it required a small proprietary power supply from Dell. However, with the case open I was able to connect a standard sized atx power supply for testing. Even with my known good power supply I was still able to reproduce the problem. Even though the memory test passed I took a second look. The system had 2 memory slots with a 128MB stick in each slot. I removed one stick and was not able to reproduce the problem. I then swapped the one I removed with the one in the system. Still I was not able to reproduce the problem. Next I put them both back in again. Problem came back. This told me it was either the motherboard or the processor. The fan on the processor was functioning fine. So my best educated guess was it was the motherboard. The system was out of warranty but the Dell motherboard was going to be the only replacement. Dell sold the customer a refurbished motherboard for about $120. I left the computer on the bench for a week running with only one stick of ram while I waited on the replacement board. It never once rebooted the whole time. I replaced the part and the customer hasn't had any problems since.

Next time I run into that I'll know what it is right? Nope! Gotta start all over and troubleshoot the problem to rule out as much as possible.

If you have a known good power supply and other parts laying around you can test some of these things yourself. Otherwise you might just be better off having someone look at it. There's no definite single thing I could say that's the problem based on that symptom though.

 

[QC]

Re: Help please. Computer reboots on it's own?

Next time I run into that I'll know what it is right? Nope! Gotta start all over and troubleshoot the problem to rule out as much as possible.

Same as an engine . . . On second thought, maybe I threw that PC in the bin

 

[Mark42]

Re: Help please. Computer reboots on it's own?

The one time I had a random reboot problem it was becasue of lose connections. Check to be sure the ribbon cables between main board and drives are seated tight at each end. Also check memory chips to be sure they are seated well. Sometimes a connection will work until the PC warms enought to make components expand and the connection is lost for a fraction of a second, and bingo! the pc reboots.

If that doesn't fix it, the problem could be main board like i386 said.

 

[Boomyal]

Re: Help please. Computer reboots on it's own?

I have two identical PIII's with 450 mhz processers. For kicks I upgraded my primary unit to a 750 mhz. My other unit is was used for my work programs. The 750 worked well for some time then just started randomly shutting down. The 750 mhz was the fastest cpu authorized for that board. I figured that it just overheated the MB and shut down when a circuit got too warm. I just sidelined it, what? 4 years ago and went an built a P4 @ 2.4 ghz. That's what I am using now. It is already an antique but never has problems. I'm beginning to get paranoid.

The other 450 is still running today. I never shut it off and it just keeps ticking along. I put the HD from the 750 into the 450 so I had extra backup capability. I still have the carcass of the 750 for parts in the event my 450 work unit goes **** up.

 

[ndemge]

Re: Help please. Computer reboots on it's own?

I had been fighting this problem for the last 6 months on my basement file/music server. This computer also has the printer connected to it.

Every day or so the computer would be off. I would notice it when trying to ftp in, or get to my files.

I was about to take it to work and start babysitting it while swapping parts as 386 did.

Then one day, I was downstairs when someone tried to print. Turns out, the ups would flicker for a second when the laser printer would go into warm up (1800kva ups) Turns out the batteries are shot.

This took a LONG time to figure out, because the computer would receive the print job, send it to the printer's memory. The ups flicker was long enough for the computer to shut down, but not long enough for the capacitors inside the printer to die and loose it's memory, so it would still print that job, but the next time you'd go to print, nogo, machine was off.



Personal experience for this problem has always been ram/motherboard/power supply. If you find that you have a bad ram slot like 386's had, one option is to jus put a larger stick in the other slot. This is an option for a home computer, but not a good option for a business computer.

 

[i386]

Re: Help please. Computer reboots on it's own?

Then one day, I was downstairs when someone tried to print. Turns out, the ups would flicker for a second when the laser printer would go into warm up (1800kva ups) Turns out the batteries are shot.

Yup, interesting you brought that up. As a general rule I never connect laser printers to a UPS because they draw so much current. It's not uncommon to see lights dim when those things kick in. It doesn't take a big printer to do it either. They significantly reduce battery life and pretty much negate any power conditioning the UPS offers.

 

[SeaKaye12]

Re: Help please. Computer reboots on it's own?

I used to have a Gateway that worked faultlessly for 5 years, and then started the re-boot thing. I asked a few trusted people what to do.

Their consensus was: very carefully raise the CPU box three feet off the desk and gently slide a new one in under it.

Sometimes that just makes the best sense.

Thanks for reading, Chuck

 

[Surge]

Re: Help please. Computer reboots on it's own?

i had the same exact problem a year ago. Mine would also just reboot all of a sudden. I ended up testing ram, the power supply, and was told the motherboard was fine. My problem was solved when i replaced my hard drive it hasn't failed me yet. You might want to check that if all else fails

 

[bruceb58]

Re: Help please. Computer reboots on it's own?

Like 386 said, it can be many things. I have had a few problems like this. One time it was the power suply and another time it was the graphics card. In the case of the graphics card, it failed because the coling fan on the card itself failed causing the graphics processor to overheat.

 

[rwise]

Re: Help please. Computer reboots on it's own?

yep can be many things, I have seen hard drives, CD drives, motherboards, power supply(s), RAMM, power cords, even cables not seated well, all do the same thing!

 

[bruceb58]

Re: Help please. Computer reboots on it's own?

My work computer was rebooting itself today...hard drive!

 

[Coors]

Re: Help please. Computer reboots on it's own?

Sometimes running chkdsk will help, as there are bad sectors. You would think, for the $, that we could get better quality.. But they are working on flash for hard drives-that will be sweet.

 

[bruceb58]

Re: Help please. Computer reboots on it's own?

Sometimes running chkdsk will help, as there are bad sectors. You would think, for the $, that we could get better quality.. But they are working on flash for hard drives-that will be sweet.

You mean "Large" flash drives. Only thing holding flash drives back right now is price of the chips. That will be going down though once processes are perfected.

 

[dolluper]

Re: Help please. Computer reboots on it's own?

I would replace the cheap bios battery before I replaced the whole board at least give it a shot

 

[12Footer]

Re: Help please. Computer reboots on it's own?

Wow!! thanks for all the sugestions. this is the best site on earth!
QC, it's probably a coinky-dink, but Carol's puter is also an HP. So when I get the time, I'll start there on the troubleshooting.
Problem is, it does it so infrequently -- and for no apparent reason, that "troubleshooting" isn't actually possible... Dont ya just love intermittents electronic problems?

 

[i386]

Re: Help please. Computer reboots on it's own?

Dont ya just love intermittents electronic problems?

Yea those are the worst right behind data loss in my opinion. I really hate to get a new customer with an intermittent problem. They generally treat you like you're incompetent because you don't instantly know what's wrong.

I'm swamped right now at work. I've got customers that have been waiting for a week while putting them off to put out fires. I've got one right now that's randomly blue screens that I have only been able to reproduce 2 times in the 2 trips I've made to her office. She's ringing our phones off the hook with her "emergency". I'd love to let her ride with me for a week and learn what an emergency is. We're probably gonna do a wipe and reload on Friday. I'll bring doughnuts so it'll be a hoot for all.

 

[mbroome]

Re: Help please. Computer reboots on it's own?

Im a pc technician for a university in ms for a living. We have this problem quite often. We strictly use dell pc's at the university. Look at the cpacitors on the motherboard. Are they swollen, split or leaking? If so, thats yer casue. Call dell and give them the serial number off of the white sticket on back of your pc. Regardless of the machines warranty status, they will replace the motherboard!

 

[i386]

Re: Help please. Computer reboots on it's own?

Im a pc technician for a university in ms for a living. We have this problem quite often. We strictly use dell pc's at the university. Look at the cpacitors on the motherboard. Are they swollen, split or leaking? If so, thats yer casue. Call dell and give them the serial number off of the white sticket on back of your pc. Regardless of the machines warranty status, they will replace the motherboard!

EXCELLENT suggestion! I have ran into this problem on el-cheapo motherboards. I know exactly what you're talking about. I will check that on my problem customer's system and 12footer should too.

12footer, like mbroome said...

Look at the capacitors on the motherboard. Generally the ones that give us problems are located near the processor, but check them all out. The tops of the caps should be flat. If any of them are dome shaped they are bad. If there's any crusty yellow-brown stuff leaking out (or anything else for that matter) they are bad and will cause stability problems.


mbroome, welcome to iboats forums. I think you would be an asset to the Non-boating Technical Topics Forum. I hope to see you back again.