[SOLVED] Aged PC Switches on fine one day but not the next...

[Frank Sebem]

Hi all

Before I begin...Please allow me to tell you that I am referring to an Old PC that runs a simple but very Vital piece of hardware at my work.

So, last week we turned the PC on and it was dead. So, I looked on Ebay and bought a new PSU. Bear in mind the machine is an old NEC POWERMATE VL5 from 15 years ago. So, I changed the PSU and all was good. Fast forward 5 days and I was on holiday and my colleague rang me and told me that the machine wouldn't switch on again on Monday. Not knowing what to do he left it until Wednesday and Lo and behold it switched on again...So he tells me "When you have left the machine for a couple of days it works again". I'm thinking...Impossible. If it's dead it's dead. So, come last Friday and again the PC won't turn on. I suspect a faulty PSU again and buy a new one off Ebay for £10. I brought the machine home for the weekend and left it on the Kitchen side. So tonight I was going to replace the PSU again but Lo and behold the machine has just bloody started with no problems...

What could the problem be? I assume that if the board is dead nothing will work. There are no beep codes. So, I took the case off the PC and when I press the power switch both the PSU fan and CPU fan both spin. When I did this last week none of the fans spun.

I'm very baffled how the PC can work one day. Doesn't switch on the next day. Wait 2 days and it switches on again.

Any ideas what the problem could be guys? I assume if it was a memory problem I'd hear beep codes? I assume it's nowt to do with the drives because of the fan spin/not spin scenarios...

 

[DSzymborski]

Could be a junky PSU. PSUs bought off Ebay for £10 have a tendency to be about as reliable as a Mercury Topaz you find on Facebook for $75.

 

[Frank Sebem]

Yes, I get that but I already changed the PSU the other week. This one that I just bought for £10 off Ebay I have not yet installed it because as I said the machine just switched on...

 

[ex_bubblehead]

Swapping one piece of junk PSU for another isn't going to fix anything. In addition, over a 15 year period electrolytic capacitors will age and no longer function as they did when new. This will affect both PSU and motherboard. They may even start leaking. At 15 years that PC is really beyond its useful life. If it's that important to your company then it should have been replaced/updated/upgraded years ago.

 

[jonnyguru]

What could the problem be? I assume that if the board is dead nothing will work. There are no beep codes. So, I took the case off the PC and when I press the power switch both the PSU fan and CPU fan both spin. When I did this last week none of the fans spun.

I'm very baffled how the PC can work one day. Doesn't switch on the next day. Wait 2 days and it switches on again.

It's the motherboard. Look at the motherboard for any swollen capacitors.