Dead PC ?

will0812 · 7 Nov 2011 at 19:48

Hi, Was wondering if someone more experienced than myself could help me.

Basically I have an old PC which wont boot, it doesnt even POST I believe as there are no beeps at all.

When I turn it on, it does power up for about 5 seconds before turning itself off again. In this time, none of the case fans start up but the cpu fan does.

As there is some life, I am assuming its not a power supply fault ?

I have now stripped out most of the components, Sound Card / GFX Card / HDD / Memory, and after each removal tested again with no luck.

To me it seems to be either down to the motherboard or CPU, but is there any way to tell which. Or does this information suggest something else is wrong?

Thanks

Hyburnate · 7 Nov 2011 at 19:52

Sounds like CPU. Try each stick of RAM vice versa

will0812 · 7 Nov 2011 at 20:10

Yea I tried with one stick, and with none (And got the same results), I didnt try the 2nd stick on its own though, which I will soon. You dont think its PSU then?

Luke · 7 Nov 2011 at 20:23

Could be PSU or MB. Hard to test unless you have another PSU you could use though.

will0812 · 7 Nov 2011 at 20:43

Would resetting the cmos battery help at all?

RJC · 7 Nov 2011 at 20:51

will0812 said:
Would resetting the cmos battery help at all?

It would be worth a try, what is the spec of the pc.

Jamiman · 7 Nov 2011 at 20:51

Wont do any harm...although don't know if it's any good.

I think either CPU or mobo is the issue in this case S:

Purgatory · 7 Nov 2011 at 20:55

When you say old pc , how old and what is the specs ? Could even be something as a simple new CMOS/BIOS battery and it may boot up, I have seen boards refusing to POST if the battery on the motherboard had failed or died. I would reset the BIOS back to factory (read the manual to locate where to do that normally is 2 pins to short-out or read the motherboard in good light to find them they normally have some writing near the pins). Then I would only have the CPU, RAM installed and see if it stays on when you power it (if it goes off take the RAM sticks out and try again, if failing again it could be a motherboard or CPU or the PSU at this point I would think it is the motherboard because they don't last forever and the capacitors age, but normally a motherboard will show signs before totally failing like not starting up 1st time or just freezes and gets worse over time and fails totally), if it does stay on add the graphics card and test again for the same it might even work at that point, so then add the rest of the parts hard drives, optical drives, sound cards etc.

will0812 · 7 Nov 2011 at 20:59

Erm. The PC is about 5 years old now. But hasnt been used for the past year or so due to not working. Think it has an AMD X2 5000 CPU, couldnt tell you exact MB but socket AM2 obv. 500W Nexus Power Supply, 9800GTX card i think... I have now removed the cmos battery, how long does it take to reset ? And i will try to restore the bios if this doesnt work.

will0812 · 7 Nov 2011 at 22:40

Pretty sure i managed to reset the cmos, and still nothing. That means its the MB most likely then ?

Purgatory · 7 Nov 2011 at 23:47

Yes now you need to find a spare PSU to make sure it's not the PSU, that is the next test I would do. If same again could be the motherboard or the CPU or the Ram, so after testing the PSU and still fails I would test the RAM, if the RAM causes same problem it will most likely be the motherboard not the CPU, CPU's are bullet proof aslong as you dont overclock and overvolt them wrong.

will0812 · 8 Nov 2011 at 00:09

Ok thanks, I will attempt to test with another psu in the morning. I dont think its the ram as i have tried both sticks on their own, in different ram slots and still the same, its also the same with no ram installed at all. And the cpu has never been overclocked. Was used a lot for about 3 years with no issues and then not used much since. So most likely will be the MB i guess ?