Question My old PC some times turns on and sometimes not

nofanneeded

Respectable
Sep 29, 2019
1,541
251
2,090
Hello ,

I have an old PC around , using it for firewall , it is first gen i7 PC.

It is behaving strange , some times it powers on and works normally , and some times it does not ... like a dead PC ...

is it dying ? I replaced the Bios Battery , but did not solve the problem.

Please note that if I keep trying it start up but some times takes 30 minutes of trying when it happens.

Is it onboard Capacitors problem ? or Power supply Problem ?
 

Ralston18

Titan
Moderator
Windows?

Update your post to include full system hardware specs and OS.

The mext time that the old PC does boot look in Event Viewer and Reliability History for error codes and warning associated with the failed starts. I.e. some software problem but I think hardware is more likely.

Could be the power switch or it could indeed be the PSU.

Or just a loose connection inside. Noted that you replaced the CMOS battery.

Did you also clean the system and then reseat all cards, RAM, jumpers, and cables? Ensure that all are fully and firmly in place.
 

nofanneeded

Respectable
Sep 29, 2019
1,541
251
2,090
Windows?

Update your post to include full system hardware specs and OS.

The mext time that the old PC does boot look in Event Viewer and Reliability History for error codes and warning associated with the failed starts. I.e. some software problem but I think hardware is more likely.

Could be the power switch or it could indeed be the PSU.

Or just a loose connection inside. Noted that you replaced the CMOS battery.

Did you also clean the system and then reseat all cards, RAM, jumpers, and cables? Ensure that all are fully and firmly in place.

Thanks for your reply ,

The power switch is fine because it lights on when the PC refuses to start up.

The cabels and cards are cleaned and connections are okay.

I have the feeling that the capacitors in the PSU or on the motherboard are slowly recharging leading to this problem ... because when the system runs it runs perfect no errors. Just the start up either it post or not.

Please note that when it does not start up it wont allow me even to reach bios . Just the power fan spinning and the light on the switch button is on.
 

Ralston18

Titan
Moderator
I am going to stay at a "field repair level" (no soldering) and set capacitor issues/causation aside.

Likely heat/temperature related. Nothing happens until some component gets warm enough to fully work.

PSUs are not designed to be fixed by end-users. Not recommended unless there is has been specific relevant training to do so.

As for the light on the switch, it can indeed light up and the PC not start.

Hardware specs?

Especially the old PSU. Make, model, wattage, age (years), condition?