Computer can't turn on for 40 minutes after a shutdown.

DHS Odium

This one is odd, my nephew built his first computer, it's a beast, but it has a problem. In fact this problem has been going on since he bought it, well over a year ago, so any warranty is now up. He's a lazy jerkface so now I'm going to try to troubleshoot it knowing returning any part is not an option.

I'm going from memory here on what's in it, and I can update later when I get a better look, but here's the computer and the issue:

AMD Phenom quad-core, with some motherboard
4GB ram (2x2GB 800mhz)
some powerful video card, I'm gonna say ATI Radeon 4890
Sata hdd, ide dvd burner
Wireless G internal PCI card

Not too specific but the problem is unique: sometimes, after a shutdown or a reboot (which doesn't restart) the computer will not come back on unless you wait 40 minutes. You press the power button, fans spin - no system beep, no case lights, nothing happens, other than knowing power should go through (and is on because of the fans and lights on the motherboard and gpu). It's not posting I guess. But according to him it seems more time based. It won't come on, if you try it again in 10 minutes, and still nothing, you have to wait another 40 minutes or so.

Now, this isn't all the time, but he says the most reproducible way is letting it go to sleep. It will not wake up from sleep, ever, it will always do this. Last night I took out all the nonessential parts to help troubleshoot it, and while I got it to boot, I missed getting into the bios to check settings, and when I restarted it again it wouldn't come back up. It's at my place so I plan to switch out more things like RAM and video card. My guess is it's the power supply, but I'm really not sure, I haven't heard of anything like this.

Before thinking it was the power supply we thought it was heat related, and while after he built it it did crash, redoing the thermal paste solved that, and the computer never crashes in a game or the desktop - this issue is strictly with shutdown, reboot, and always with sleep - which he's disabled because of it. He's also run heat monitors and system and cpu temp is normal. Operating system is Win 2008 Server R2 (essentially Win 7), and before that it was the Win 7 Beta and then RC - OS shouldn't have anything to do with this though.

Any ideas, or suggestions beyond what I'm already planning?

Bionic Monkey

If it's not even posting, my suspicion is the motherboard.

vegas-steven

It's almost entirely the motherboard and most likely it is a capacitor.
You can start on the cheap by trying a new from the box power supply to see if that is where the problem is starting but read on:

I repaired a computer for someone who complained his tower would not turn on unless the room was cool. He said once on it would run but after it would restart often would need to be left off for a while and then would come on.
He also said that at night the pc would have problems booting but in the mornings would start up from a cold boot (as in the old term like a cold start on a car - it hasn't been running before the boot up) just fine.

Replaced the power supply and all was well for three months until he returned it to me and I could clearly see a capacitor on the board was buldged and popped. Dead motherboard meaning be motherboard required.

The power tries to flow through the board and then stops to prevent damage tothe CPU etc.

Sounds like your problem.
Motherboards are cheap most of the time and what was top if the line 3 months ago could even be 50% less dollar value now.
eBay and newegg and swap it out but start with a good quality power supply in the $50 range.

Good luck!

exoplasm

I have had a similar problem recently. Removing some of my RAM would allow me to boot, but my system was really unstable and sometimes it would take a few minutes before it would POST.

I swapped out the motherboard with the same model (which is no longer sold locally, had to pay extra online, urgh) and everything is working perfectly.

See if you can RMA the motherboard if you're not brave enough to solder things.

DHS Odium

Here's an update after running some more tests:

I swapped out the motherboard with another I had in a spare computer. I got it to boot just fine, over and over again and any shut down allowed me to immediately start back up. Problem solved... or so I thought. When trying to do a fresh install of Windows 7, I left about 80% of the way through to eat dinner. When I came back the screen was blank, but the computer was on. There was no way to wake it or any response. I turn it off from the power supply (it's worth nothing when this problem occurs the power button does not work, even holding it down for a long time - which normally restarts when the computer is actually functioning). Well, shit, it doesn't come back on. Same problem as the other motherboard, it turns on, everything powers up, but a black screen, and no beep to indicate the POST. I try this several more times, same thing.

Then I figure, it must be the power supply. I quickly unplug the mobo connectors and hook it into the power supply from the computer I took the spare motherboard out of, and plug it in - though I had to unplug the video card, disc drive, and hdd because it's much lower power (230w vs 500w). It boots right up until it tells me to insert a system disc since the drive was unplugged. Further adding to my power supply theory.

Then, I plug the old PSU in again one more time... and it boots right up. So is there an actual issue here? Is it just not giving enough power, since it booted with the gpu unplugged among other things? It wouldn't explain why it ran somewhat okay for a year, with even more stuff plugged in.

The next step I'm going to take is get an actual replacement PSU to use. The mobo has been swapped and while it seemed to work for a time, after an hour or so, in the middle of installing Win 7 (or perhaps during one of the reboot during an install) it started having the same issues as the old mobo. Could the processor be doing this? It's a Phenom 4 core processor, when I first put the new board in I left the Athlon in there for awhile with no issues. I put the Phenom in and again had no issues, but it was in there when the problems started again. It also runs a little hot (52c idle with case open, to be fair it was 78F in the apartment).

Another interesting thing - I noticed it takes significantly longer sometimes to POST (with new or old board) when the IDE DVD burner is plugged in. And in a few cases it didn't boot at all, most times it was fine though.

exoplasm

52c idle? May want to replace the thermal material between the processor and the heatsink.

corky842

exoplasm wrote: »

52c idle? May want to replace the thermal material between the processor and the heatsink.

Hell, cheese should do better than 52c (assuming you have a good heatsink/fan).

Paladin

your power supply is weak and it should be ashamed

replace that first; there's obviously some unacceptably low volts coursing through somewhere

DHS Odium

Update: It was the power supply. Not because it was weak though, we put in a 400watt one instead, everything is working perfectly now. All the things he couldn't do before (put the computer to sleep, use power button to turn off) are working now. Also I re-spread the thermal paste (he had put too much on clearly) and it idles now at 39C with the case closed, 33C when open.

The old power supply is just plain broken. We need to make sure the new one will be powerful enough though, next up is running it for an hour or so on an intensive game.

vegas-steven

DHS Odium wrote: »

Update: It was the power supply. Not because it was weak though, we put in a 400watt one instead, everything is working perfectly now. All the things he couldn't do before (put the computer to sleep, use power button to turn off) are working now. Also I re-spread the thermal paste (he had put too much on clearly) and it idles now at 39C with the case closed, 33C when open.

The old power supply is just plain broken. We need to make sure the new one will be powerful enough though, next up is running it for an hour or so on an intensive game.

So you read my post then? The one that said start with a good psu and go from there

GrimReaper

Pity I only just saw this, a couple of years ago I had a pc that had the exact same issue and identified it as the psu. Most power issues usually are, in my case it was a 550w Antec Truepower. (which i'd like to add I don't buy Antec psu's anymore as i've had this happen with multiple Antecs when also bought for work)

DHS Odium

Ha, this was a 500w Antec.