temporary boot problem

PiKo · 03 Oct 2016

My desktop PC is dualboot with two SSD's and HDD. It ran for a long time without problems. This morning the PC suddenly stopped working and my monitor told me: no signal. Several restarts did nothing. Waiting for half an hour and starting up did nothing. The PC refused to boot. No messages, dark screen.
Trying to boot from a recovery disk: The DVD did close itself during startup but the recovery disk did not spin. No booting possible, although the DVD is the first booting device.
My conclusion: hardware failure or serious Bios problem, so we go to the PC shop.
After an hour in the PC shop, after several restarts suddenly everything started working again. No problem anymore.
Check 1: was there a disturbing Windows update: no; check 2: something to see in the error logs: no.
Although everything works now, I am wondering what has happened and what could be a possible cause. Was it just a long time waiting that some (boot?)memory could reset itself? Or possibly a lingering hardware issue? Thanks for ideas.

EdTittel · 03 Oct 2016

My best guess is a transient or intermittent power supply (PSU) problem. Contact your shop and ask them if your $30 fee will include a quick bench test of your power supply should this problem recur. If so, you can exercise that option if and when it happens again. If not, you might want to consider buying this $18 part from Newegg: Rosewill RTK-PST - Digital LCD Power Supply Tester-Newegg.com. You'll have to take your PC pretty much apart to use this thing to check your power supply, but it will tell you if it isn't working properly on one or more of its output rails. If you work on PCs, or build your own, it's something worth having for your toolkit anyway, and it's not terribly expensive.
HTH,
--Ed--

PiKo · 04 Oct 2016

Thanks for your suggestion; I will keep it in mind when it happens again.
Still a question: my desktop is 5 years old (and still very fast). Could it be an effect of the end-of-life of the CMOS battery? However, with other people's PC's, I saw the end-of-life causing wrong dates/times and that was not what happened here.

LMiller7 · 04 Oct 2016

It is hard to imagine this as anything but a hardware problem. A bad or failing CMOS battery could not do this. Most likely suspect would be the PSU.

EdTittel · 04 Oct 2016

Agreed. That said, CMOS batteries cost a couple of bucks. They're easy to swap out. If you're game to try, it won't take much time, money or effort to make that happen. One big BUT: you'll lose all of your current BIOS settings if you swap out the battery. If you've made any alterations to the BIOS, you should take a snapshot and save it to a file, and learn how to replace the default BIOS with your customized version. OTOH, you can go through all the screens and record all settings, then restore them by hand. I prefer the record and replay method because it's less work. Do as you see fit!
HTH,
--Ed--