Dead CPU or Motherboard

[TheGamingKiwi]

Hi Everyone,
My friend and I were repairing a pc the other day that wouldn't boot up. It would turn on for a few seconds then shut back down again. Eventually we got it working by replacing the power supply. Then we got the steady amber light (the pc is a Dell Dimension e521), so we reset the bios and that got it working for a bit, but then it happened again. So we removed the CPU's heatsink, and removed and replaced the CPU. But the CPU was stuck to the heatsink from dried thermal paste, so we had to remove the CPU from the heatsink, which was fine, but we had no thermal paste to put back on. So we just put the CPU back into the slot and reattached the heatsink. Then, miraculously is WORKED! It worked for about 1 hour then shut down again. We then realised we hadn't screwed in the screws on the heatsink, it was just sitting there. So we did that and then it worked fine again. We had it running for about 2-3 hours and was in the process of installing Windows XP, when it turned itself off, but when we turned it back on it was fine. It then kept doing that and eventually we turned it on and it gave us the deadly amber light on the front panel. So we took the Bios battery out over night and put it back in the morning, but it didn't work. I then tested the Graphics card on another PC and it works fine, the RAM is fine, and the PSU is fine. So we have came to the conclusion that is the the CPU or the motherboard. We reckon it is the CPU because of the following reasons. When we had it working normally it shut down a couple of times and said shut-down because of thermal problems, and the CPU fan would sometimes go ballistic. Also, we had no thermal paste applied so we reckon we may have overheated and fried the CPU. But the annoying thing is, when we turned it on with the amber light and left it running, the CPU would heat up slightly but it took ages and it didn't get that hot (this is also without heatsink and fan).

If anyone has an answer it would be greatly appreciated. Sorry about the long post, but I want to make sure I have described everything in detail so you guys know the exact problem, which then could help me get my PC going. Thanks in advance

 

[Mouldread]

Man...

it's like your car engine oil leaked out and you couldn't be bothered to put new oil in and drove the car until it stopped and now you want to know what part of the engine is cooked.

It could be the CPU, it could be the Motherboard and there is a sligh chance that you have not damaged anything at all if the failsafe overheating protection managed to shut your PC down before damage was done.

Clean the CPU and the heatsink well and make sure there isn't any residue on the motherboard. Buy some thermal paste, apply roughly a pea-sized amount on the CPU and place and secure the heatsink and hope it works. There is no way to know what part has been damaged if you don't try them in another PC. But to be honest after all that you have done to the PC - including trying to turn it on without the heatsink even being attached to it you should probably stay away from fiddling with PCs lol.

 

[Paul NZ]

Yup, buy some thermal paste and put it on. Otherwise it'll probably overheat / fry it

 

[TheGamingKiwi]

Man...

it's like your car engine oil leaked out and you couldn't be bothered to put new oil in and drove the car until it stopped and now you want to know what part of the engine is cooked.

It could be the CPU, it could be the Motherboard and there is a sligh chance that you have not damaged anything at all if the failsafe overheating protection managed to shut your PC down before damage was done.

Clean the CPU and the heatsink well and make sure there isn't any residue on the motherboard. Buy some thermal paste, apply roughly a pea-sized amount on the CPU and place and secure the heatsink and hope it works. There is no way to know what part has been damaged if you don't try them in another PC. But to be honest after all that you have done to the PC - including trying to turn it on without the heatsink even being attached to it you should probably stay away from fiddling with PCs lol.

Hi Moulread
Thanks for your answer, would it be worth buying a new cpu and thermal paste? I don't mind buying a new one because the one that is in the machine sucks.

 

[Paul NZ]

You could buy another CPU, but make sure the BIOS on the mobo supports it. Otherwise its not going to turn on

Thats if the CPU that was in it still exists

 

[Mouldread]

I wouldn't waste money on a new CPU before you know for sure what part has died if any. Buy some thermal paste, clean the CPU/Heatsink and aplly the paste. Then reset the CMOS by using the appropriate jumper on the motherboard or by removing the battery and see if it works. If it doesn't then you will have to find another PC with the same socket and try the CPU there. If the CPU is dead you still can't be 100% sure that the motherboard hasn't also been damaged so the next step would be to try the motherboard with a CPU that you know definitely works.

It's a time consuming job but at least you won't have to spend money on it. If you just bought a new CPU and it turns out that it was actually the motherboard that was fried then you would have wasted the money on the CPU and will also need a new motherboard.

 

[TheGamingKiwi]

You could buy another CPU, but make sure the BIOS on the mobo supports it. Otherwise its not going to turn on

Thats if the CPU that was in it still exists

Surprisingly, you can buy CPU's for the E521 still.

 

[TheGamingKiwi]

I wouldn't waste money on a new CPU before you know for sure what part has died if any. Buy some thermal paste, clean the CPU/Heatsink and aplly the paste. Then reset the CMOS by using the appropriate jumper on the motherboard or by removing the battery and see if it works. If it doesn't then you will have to find another PC with the same socket and try the CPU there. If the CPU is dead you still can't be 100% sure that the motherboard hasn't also been damaged so the next step would be to try the motherboard with a CPU that you know definitely works.

It's a time consuming job but at least you won't have to spend money on it. If you just bought a new CPU and it turns out that it was actually the motherboard that was fried then you would have wasted the money on the CPU and will also need a new motherboard.

I do not have a motherboard that supports the type of CPU, so I think I might just bite the bullet and by a new CPU, and worst case scenario I will have to buy a new mobo:/

 

[Paul NZ]

Is it an AMD system? If it were Intel it probably wouldnt have fried. If it's dead

 

[TheGamingKiwi]

Is it an AMD system? If it were Intel it probably wouldnt have fried. If it's dead

Yeh, it's an AMD processor. It is quite old as well.

 

[Paul NZ]

Used to have one a 754. But thats long gone now. Someone gave it to me after they had updated to something newer

 

[TheGamingKiwi]

Used to have one a 754. But thats long gone now. Someone gave it to me after they had updated to something newer

Do AMD have a tendency to burn out more than Intel?

 

[Paul NZ]

Yup heres a video https://www.youtube.com/watch?v=qSdcMqWM1DE

I would say Intel would have better thermal protection. If thats what you mean. As in overheat

Intel CPus now would shut down a system if it got too hot. Dont know about AMD CPU's now, never had one long enough to find out

The 3 PC's I built are all Intel. 2.5/2.8 and the new build 3.1. I've never built an AMD from scratch. I usually get Intel based boards/CPU's