PC very delayed POST if at all

Giarc86

Giarc86

Expert Member
Joined
May 28, 2008
Messages
1,243
Reaction score
4
Hi all, having a strange issue with my PC where the fans and lights come on but it won't POST immediately. Sometimes if I leave it on it will POST after a 10 or 15 minutes wait. Other times it doesn't POST at all.

I have removed most components and tried to boot with just fans, cpu and 1 stick of RAM but still the same result. Interestingly if I try the second and fourth RAM slot the PC just switches off and on continuously. The first and third ram slot will sometimes boot but only after a long wait.

I checked the PSU with a multimeter and everything seems to be okay there so I am assuming this could be a MB issue? I find it strange that it does boot after sometime as surely if there was a MB issue it wouldn't boot at all?

Wanted to see if anyone could shed some light on this? I did Google but my specific use case doesn't come up.
 
Unplug everything, including connectors/cables.

When unplugged, press the power button a few times, as if switching it on.
Power will flush.

Connect it all again and see if there's a difference. If it had no effect, clear CMOS and test with defaults.
 
Ryansr said:
Could perhaps update the bios and see what that does.
Click to expand...
BIOS updates should only be done if everything is working well.

Attempting to update now, could corrupt the BIOS beyond repair. Especially if it has no backup BiOS or BIOS recovery options.
 
Ryansr said:
Look, I was just suggesting a possible fix. As you were.
Click to expand...
It's not a good fix, given the problem.
Don't feel offended. We are sharing experience and knowledge.
 
If you switch off AC power, then switch the AC power back on, but do not start the pc for two minutes, then press the start button, what happens now-?
 
Ryansr said:
I was not the one who was triggered.
Click to expand...
Then who was triggered?
You assume I'm triggered because I correct you. That's far from being triggered.

Check your panties. It might be your time. Since you are a little bitch.
 
Try a new PSU and see if it makes any difference.

Could be leaky caps on the PSU. You would need a scope to check it properly. Repaired one the other day where the PC would intermittently not power back on from hibernation. Always thought it was some Linux bug but turns out a bulging cap on the PSU caused startup issues with unstable voltages.

Don't attempt to fiddle in the PSU if you don't know what you are doing. There are some caps that store 400V for a while.
 
gregmcc said:
Try a new PSU and see if it makes any difference.

Could be leaky caps on the PSU. You would need a scope to check it properly. Repaired one the other day where the PC would intermittently not power back on from hibernation. Always thought it was some Linux bug but turns out a bulging cap on the PSU caused startup issues with unstable voltages.

Don't attempt to fiddle in the PSU if you don't know what you are doing. There are some caps that store 400V for a while.
Click to expand...
Actually more likely there is a bios conflict with the posting process, most MB's these days have dual bios in the event of corruption or bios conflict. More then likely the cause. I have experienced this before, it simply requires resetting the bios and removing the bios battery for a few minutes as well as CMOS jumper.

Iam still using the same psu years 3 years later, it isn't always the worse case scenario, considering he used a multimeter on PSU confirms that there isn't a issue.

Additionally a PSU issue will not result in taking a long time to post it will either not turn on at all or switch off immediately, power cycling is often not always related to the psu, in the event of psu power cycling is the result of not supply enough power to a particular rail example 3, 5 and 12 volt rails.

In the event of a leaking cap it would have almost instantly blown a fuse on the psu, pending the quality of the psu and specific tolerances of the under and over volt protection, in conjunction of the rectifying bridge generally would cut out the moment you turn it in on, psu power cycling does happen but not that often, that I would consider it to be an issue here as the op pointed out the PC running for 15 minutes trying to post and not cycling.

Most likely not a psu issue.
 
Archer said:
Could be a capacitor on the motherboard that's reaching the end of it's life. Check them all for bulges, swelling and/or cracks.
Click to expand...
I did have a look at them but couldn't seem any that were bulging or cracking. Might need to remove the motherboard completely and have a decent look.

|tera| said:
Unplug everything, including connectors/cables.

When unplugged, press the power button a few times, as if switching it on.
Power will flush.

Connect it all again and see if there's a difference. If it had no effect, clear CMOS and test with defaults.
Click to expand...
I did give this a go but no luck either. Removed all cables, cleared CMOS and removed the battery but same result.

Ryansr said:
Could perhaps update the bios and see what that does.
Click to expand...
The BIOS is on the latest version already. There are beta versions but I don't want to mess around with those.

Moto Guzzi said:
If you switch off AC power, then switch the AC power back on, but do not start the pc for two minutes, then press the start button, what happens now-?
Click to expand...
No difference unfortunately.

wizardofid said:
Actually more likely there is a bios conflict with the posting process, most MB's these days have dual bios in the event of corruption or bios conflict. More then likely the cause. I have experienced this before, it simply requires resetting the bios and removing the bios battery for a few minutes as well as CMOS jumper.
Click to expand...
I have tried removing the battery and setting the CMOS jumper but it hasn't helped.

Thanks for all the replies. Seems it is most probably the motherboard that is starting to go. Wanted to check if anyone else had had a similar issue which might have been an easier fix. Probably time for a new PC as it is anyway :)
 
Firstly:

What hardware have you got?
What MB/CPU/PSU/RAM/GFX what are you using?

Slow POST can be everything from memory training, all the way to poor current delivery towards the components.
It's always a good start to reset the BIOS. I would absolutely then try each stick of memory you have individually in slot 1, and see if you can narrow it down to memory issues.

Heck, most boards will display or beep an error code when you boot without memory installed.
 
You must log in or register to reply here.
Back
Top
Sign up to the MyBroadband newsletter
X