BleepingComputer.com: Pc Restarts At Post

Hi, my PC is a Pentium 4 2.0A GHz with 256MB ram, MSI 845PE Max mobo, etc. Lately, the PC keeps restarting for no reason. It keeps restarting at the POST screen, or even when I'm in making changes in the BIOS settings. If I am really lucky, I can get to the Windows XP desktop for about 15 minutes, only for it to restart. I have ruled out the HDD, as a faulty HDD won't be a culprit for restarts at the POST screen. I have changed the power supply and the power outlet to which the PC is plugged into.

I don't see any "swollen" or "bloated" capacitors on the motherboard, and I have replaced the RAM with a new stick. Sometimes when the PC restarts, the monitor doesn't detect anything, the USB mouse light will be 'ON' and the NUM lock will be lighted and jammed for a long time.

I have also cleared my CMOS settings and have replaced the CMOS battery with a new one. The PC is quite old (5 years and counting). I suspect that either the motherboard or the CPU is faulty, but i was told that should anyone of these 2 components is faulty, the PC won't even boot up!

Any suggestions and advice will be much appreciated. Thank you!

Any signs of the restart in the Windows Event Viewer? (Start...Run...type in "eventvwr.msc" (without the quotes) and press Enter) Check the System log first, then the Applications log if you have time.

Electronic circuits are so complicated that blanket statements about things working or not working are, IMO, not valid. I have seen (at work) dying hard drives that could still boot into Windows. My son had bad RAM that would cause his system to reboot at random intervals - but would work fine most times. The circuits for an onboard device on the motherboard can be broken and won't affect the rest of the motherboard (depending on where the break is).

If you can't get to the Event Viewer, then I'd suggest starting with a hard drive diagnostic from the manufacturer of the hard drive - along with running MemTest86 from this link: http://www.memtest86.com/ (both are free)

If you're able to get into Windows long enough, try installing this free utility: http://www.sisoftware.co.uk/index.html?dir...n=sware_dl_3264
See if it indicates any problems with your system.

Also...

Next time you are able to actually get into Windows, make this change (if not already done): Disable Auto Reboot On System Crash - http://www.theeldergeek.com/auto_reboot_on_system_crash.htm

Doing this may allow some actual data to be recorded in Event Viewer re what's happening.

Louis

Dear usasma and hamluis, thank you for your advice. I will definitely try the methods listed. As for the part about the motherboard parts being broken and still working, never knew that at all! Thanks once again for the advice and I will post the results of my 'experiment' soon.

Hi, I tried to install the latest version of Sisoft Sandra. However, the Setup file requires GDI Libraries which I have to download from the Internet. At this point, the PC restarted. I'm not able to run the MemTest too, due to the random restarts. As such, I am going to conduct a trial-and-error sequence of replacing the RAM, etc. Should this fail, just have to get a new CPU.

Thanks for all the suggestions guys!

I have seen some of those symptoms when the cpu is failing, remove the hsf and look for signs of overheating, the thermal paste will have melted and flowed down

make sure the fan is operating properly and reseat heatsink with fresh compound after cleaning

Since it reboots when trying to run MemTest - it's not a Windows problem, but rather it's a hardware problem with the system. Make sure you reset the BIOS to defaults and see what happens.

After that it's a matter of disconnecting all of the hardware that you can.
If this solves the restart issues - then something that you took off was the cause.
If it still restarts, then the problem is in the stuff that's left.

My pc was randomly restarting, and i had it on one of those multi plug socket things. It was actually the plug fuse!

Chewy, as you said, I think the CPU might be failing, because I noticed that when I removed the heat sink from the socket, there was some black residue on the Intel chip. And it's not something like soot, where you can just rub it away, this thing stays there. As for the heat sink fan, it's running smoothly without any problems, including the case fans. As such, I'm gonna try and remove the black stuff on the chip and apply some new thermal compound. Will post back here my latest findings!

I pulled a HSF off a P3 once, you could see the pattern where the paste had fried then made a sagging pattern as it flowed down

that cpu was toast

I encourage people to keep the cooling running good and watch the temperature

Intel has used (at least sometime recently) a black piece of tape on the processor that I presume is a thermal tape. I took it off my last CPU and put on Arctic Silver instead (because I couldn't confirm that it was heat tape).

an associate bought an amdxp3200 for 450$ when it first came out, he used the stock hsf with that crappy white square.

it did ok for a year and a half till they moved it to a new office with no air conditioning, in the 2 weeks of hot summer weather they refused to shut it down when the room temp got above 90F, it started messing up with them and they called me

the temperature was running 85-90C at idle, the fans were so dirty I couldn't see thru them

I cleaned it up, remounted the HSF with good paste but it was too late, I got it to work(sort of) by lowering the fsb to 166/333, the next month we scrapped it for parts