CPU stopped working after CPU temp rose to 100 deg--is it from dead (overheated)

zepsite

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Apr 21, 2010
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Hello,

I am rebuilding 2 systems (out of 4 old ones). It took me 2 days to finally get one running. I must be jinxed because during this process I killed 2 working old pcs (both pentium 2s), after trying to revive them i gave up and bought an old cpu/mobo p4 to use with my old parts (mem/hd/psu/vc/casing etc) That was Rebuilt PC#1.

Now I'm on Rebuilt PC#2. Actually i wasnt even rebuilding it.. it was my old PC before I upgraded to a newer PC.

Specs:

Sempron 1.5 mhz
512 (256x2) mb mem
256 mb Nvidia geforce card
40 gig hd
OS: Windows XP

I havent used it in a while till i bought a 2nd hand monitor to use it with, so i can give it for my daughter to use. It was working fine for DAYS for casual use/testing. Had to take it apart to "borrow" the dvdrom drive for use to install OS on PC#1.

So everything was ok until the following happened:

I decided to do a clean install of XP. So i booted from the install disc.. setup runs..it loads the files.. till I reach the "Press Enter to Setup" option, the PC shuts down on its own. I did this several times, same thing happens.

I did some research and it says CPU cooling might be a prob. Checked the PC HEALTH STATUS in the bios and i see temp rising to 70. I rested the PC for hours and tried again. Same thing. I booted the PC in its current XP OS and ran speedfan. It shows 60+ range never rising to 70. (BIOS shows higher temp than Speedfan). I put a deskfan beside the open casing to help cool it and speedfan shows it lowers to 50+ temp. btw the CPU fan is working ok.

Despite this seemingly lower temp, i tried the install again and same thing happens. Then I even tried disabling the CPU temp warning in BIOS, then later setting the warning to 80 deg (i thought it was this warning that was causing the PC to shutdown) Still no luck.

Then I tried to check the heatsink to see if it was loose and if there is thermal paste still there (my first time to know what thermal paste is for). I cant tell for sure, but i said to myself i will go out to buy thermal paste later. In the meantime i replaced the heatsink and tested one more time. This time, in bios, i was surprised to see CPU suddenly 80, then almost immediately jumped to 100 deg! I turned off the PC at once, and thats the last time i can get it to boot.

Booting afterwards show CPU fan, lights on, USB mouse on, but keyboard lights not on. No pOST, No video, No beeps.

I checked the sticky here and did the following:

Disconnected everthing
Took out the memory
Took out CMOS battery
Tried 3 different PSUs

all same thing.

Im guessing its either a dead mobo or dead cpu or both?

Can i find out what so i know what used part to buy? (mobo or cpu)

and I am just curious, what do you think caused this sudden "death" of my PC? Overheated CPU? But I hear 100 deg temp is not fatal yet, and how could it jump to that high in a matter of seconds? Did my fiddling around (checking) the heatsink and cpu do it in?

In the end, I had a perfectly fine working PC, all i wanted was a clean install of an OS.. i didnt think it will lead to my PC dying as a result . :-(

And as i mentioned in the beginning, I must be jinxed bec its not the first time i killed a pc while trying to upgrade/rebuild it. All in all i killed 3 PCS out of 4. (the 4the one was already dead to begin with, I just harvested them for parts). what a bummer... :-(
 

pepperman

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Sep 15, 2009
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Unfortunately, its hard to tell which component (mobo vs. cpu) is dead, and its very possible that both are. If you're looking for replacements, I wouldn't recommend trying to revive it, as you'll end up paying more than its worth.

My guess as to how it died is you didn't properly reapply the heatsink with fresh thermalpaste when you checked it, leading to poor cooling conditions resulting in the cpu being fried.
 

False_Dmitry_II

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Yeah, you have to do the thermal paste. Especially with the old socket A stuff, those things can go pop (or really smoke a bunch) without a heatsink. Just look that up on youtube.

What I think you should do is go on ebay to the CPU + mobo section and get something from AMD in there (they generally run up to 50% cheaper than comparably performing intel stuff) pretty much just go for the same as what you had or faster up to sockey 939 because that's the last one that uses DDR1. You should be good to go for about $50 or more depending on how fast you go for.
 

zepsite

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Apr 21, 2010
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18,510
thanks for the reply guys. Yeah, i pretty much figured that PC is a goner. I just cant believe that it would be that QUICK (snap of a finger) to go. Its a D'oh! moment for me. Just for a few seconds of no thermal paste it climbs to 100 C and gets fried just like that? I'll check that out in youtube like you said.

Im by no means an expert (obviously) but I had my fair share of builds and upgrades over the years. The Cpu to mobo part is the one thing i dont like to do and usually i buy them together from the shop already plugged in. all the other pc parts im comfortable doing myself.

Its funny bec in the past ive taken apart heatsinks and fans to clean the dust from them and reapplying them without thermal paste. Must be old procies that dont need them.

I live in Asia and its easy to get old parts here. Theres a shop here that sells refurbished and old parts mostly from Korea or Japan. I just bought (for my Rebuilt PC#1) a mobo for $20 and a P4 1.7 ghz for $ 3.50! (Even by our standards, that procie is really cheap!!!) All that PC is used for is light office work (Word, Excel) a Dos program, Email Yahoo and light web-browsing by a staff of mine. I reused old SDRAM mem for that one so the mobo is cheaper.

I guess ill shell out about $30 for another intel board (DDR this time). I was going to give it to my 8 year old daughter so she dont have to use mine. That's still cheap, but still it sucks that that is still $30 i didnt have to spend if i was just more careful or left well enough alone and not tried to install a Fresh OS.

All in all i would have spent $50 to re-build 2 systems using my 4 old ones. Not bad I guess to get 2 pentium 4s working (when 4 years ago they would have cost maybe 10x that).

Anyway, thanks again for the replies guys.