Dead CMOS battery caused all my issues! :(

Neil79

Neil79

Neil79

Caporegime
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On my other PC the one I do all my writing on was playing up big time this week. It was really strange how it all started, with intermittent blue screens and when I turned the computer on at the wall, the system would power itself up without me even touching the power button... When this happened it would come up as overclocking failed as If I was hammering on the reset button or powered it down mid boot.

Suddenly on Friday I tried to power up the system and nothing was working and after about an hour it started working again, atleast until yesterday! I was up till 3am in the morning using it, but by the morning time nothing would work, no power whatsoever. I tried every combination and power supply testing and still in the times it did power up, the fans were running at half speed and all my LED lights were flicking which meant something was way off on the board.

Upon reading a reddit post I saw someone mention they had the same issue and even after clearing the CMOS and leaving the battery out it wasn't until a new CMOS battery was put in it started working.

Sure enough I got a new CMOS battery, put it up and it powered up first time, everything works as it should and is perfectly stable in all benchmarks/testing.

This is rare to happen as when a battery fails most of the time the bios doesn't save or clock is out of wack, but according to these users with the same issue, the CMOS battery can put the system into a permanent off state, meaning it's always going to stay OFF.

So there you go if you have this issue, try a new CMOS battery first!
 
I learned dead CMOS battery being capable to causing some wacky symptoms from my first PC:
On one boot it just failed to recognize floppy drive.
At next boot floppy drive was found, but HDD had disappeared and PC could be booted up only from that floppy drive which was missing during first boot!
 
EsaT said:
I learned dead CMOS battery being capable to causing some wacky symptoms from my first PC:
On one boot it just failed to recognize floppy drive.
At next boot floppy drive was found, but HDD had disappeared and PC could be booted up only from that floppy drive which was missing during first boot!
Click to expand...

I wonder if the Battery has just enough Juice to partially save the CMOS.. A bit like watching a corrupted video, half the video plays the other half stops
 
Neil79 said:
On my other PC the one I do all my writing on was playing up big time this week. It was really strange how it all started, with intermittent blue screens and when I turned the computer on at the wall, the system would power itself up without me even touching the power button... When this happened it would come up as overclocking failed as If I was hammering on the reset button or powered it down mid boot.

Suddenly on Friday I tried to power up the system and nothing was working and after about an hour it started working again, atleast until yesterday! I was up till 3am in the morning using it, but by the morning time nothing would work, no power whatsoever. I tried every combination and power supply testing and still in the times it did power up, the fans were running at half speed and all my LED lights were flicking which meant something was way off on the board.

So there you go if you have this issue, try a new CMOS battery first!
Click to expand...

This happened to me with my ASUS C6H board. As an early adopter of Ryzen, I was used to some odd happenings with memory etc. I had updated the bios several times through official and non official bios revisions. Then I had the symptoms described in the OP. I rebuilt the PC from the ground up in hardware and software, no joy. The board was only about three months old at that time, all voltages were within tolerance including the vbatt.

As a last resort, I changed the CMOS battery and all went back to normal. I usually keep a blisterpack of Duracell 2032 batteries, indeed still do, however 20 months later I have not needed to use another.

Moral: if the above symptoms appear, unwanted restarts etc. Try changing the battery. For a couple of quid it may save RMA's and heartache
 
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I'd been wondering how long these CR2032 batteries are supposed to last. Looking up on the bay, some of them advertise expiry dates. 2027 and 2028 are common dates, so maybe they are estimated to last 8-10 years. There was a Panasonic kit with exp. date 2029 so possibly 10.

Thanks to OP for the heads-up. Might be having a look at someone's dead PC soon and all signs point to mobo, so this is something I'll try.
 
Danny75 said:
I'd been wondering how long these CR2032 batteries are supposed to last. Looking up on the bay, some of them advertise expiry dates. 2027 and 2028 are common dates, so maybe they are estimated to last 8-10 years. There was a Panasonic kit with exp. date 2029 so possibly 10..
Click to expand...

Mine lasted about 4 months, however it may have been an old stock battery.

Also you're welcome :D
 
So I had a look at that PC today. Started it up and it kicked into life for a few seconds, then shut down. Trying to start it after that did nothing.

Took the thing apart and connected PSU to the board outside of the case. Just EPS cable for CPU and 24-pin ATX connected, no drives or other cables except the CPU cooler fan's, HDMI lead into the motherboard, and PS2 keyboard. Jumped both PWR -+ pins with a screwdriver and this time on startup, the CPU cooler fan kept running albeit whirring every few seconds and the PSU fan kept turning off and on (causing the whirring on the CPU fan). No display. I tried a spare working PSU and it did the same.

It was time to try replacing the CMOS battery I thought, remembering this thread. With the new battery in, evidently there was an improvement - PSU fan running constantly. CPU cooler fan running, no whirring. Thought job done. Not to be however. For the life of me I cannot get a display. I've tried both HDMI ports on a monitor, HDMI on a TV, and also inserted the GTX 1060 belonging to that PC to try its own HDMI port. Nada. Keyboard does not light up either.

I'd say that it looks as if the mobo has something wrong with it, apart from the dead battery. I'm wondering if something fried the battery and another part of the mobo at the same time, or whether the dead battery affected the mobo. Truly odd though, you look at the PSU fan running, CPU fan running, GPU fan running, and think "it seems fine now so why won't it post?"

Specs:

MSI Z87i ITX (doesn't have lights per se but the ethernet port lights are flickering normally).
i7-4770
CoolerMaster Hyper 212X cooler
8GB (2x4GB) Team Group Vulcan Orange 2400MHz DDR3
EVGA 600B Bronze PSU
Zotac GTX 1060

Any ideas on what to try, and speculation as to what may have happened, are welcome.
 
Hey Danny - sounds a PITA.

You've probably tried the below but it's easy to get wrapped up in one train of thought with a system that won't play ball.

After the battery swap did you try another CMOS reset - unplugged, deplete all power etc?.. (A second reset can sometimes remind the computer it does need to read the BIOS :/)

Also, have you double checked that it's set to PEG and not iGD - easy to miss when pee'd off.

Other than that make sure you're plugged directly into the wall.

Best of luck.
 
Plec said:
Hey Danny - sounds a PITA.

You've probably tried the below but it's easy to get wrapped up in one train of thought with a system that won't play ball.

After the battery swap did you try another CMOS reset - unplugged, deplete all power etc?.. (A second reset can sometimes remind the computer it does need to read the BIOS :/)

Also, have you double checked that it's set to PEG and not iGD - easy to miss when pee'd off.

Other than that make sure you're plugged directly into the wall.

Best of luck.
Click to expand...

Thank you, Plec. I had been thinking along the same lines re: trying another CMOS reset. No joy. Lots of unplugging and depleting too.

It is not plugged directly into the wall. With my own system in same room I needed extension leads. So I will try that later.

I wish I could enter BIOS to check PEG v iGP but I get no display at all. I know he was using the GTX 1060 last, though.

Thanks for the suggestions, Plec. Will report on how they went later.
 
With your experience Danny, I suspect your initial educated guess before even touching the board was correct.

The only other ideas i have will have crossed your mind and will have been dismissed as some are annoyingly time consuming and others dependent on having spare components to hand.

But:
  • re-seating CPU (especially looking at potential warping from heatsink around socket with such a small form factor) - small chance this could be the problem.
  • Spare PSU (if you haven't already) - can almost hear the audible groan from here if it means stripping yours :/
  • I'll end with a couple of easy ones (but i bet you've tried some already) - different stick of memory.
  • different HDMI cable - or even the dvi or DP
  • Last one is the kettle lead - try another.
Grasping at straws really, but the re-seat is annoyingly valid, but realise it will probably end up proving what you already suspect if you did it (vindication is always satisfying if not time consuming). Different PSU is always a possibility, as you know, but only suggested it as it's not mentioned - and a bugger if you haven't got one spare.

Hope you manage to salvage some of your Sunday - at least the beer will be cold by the time you get to it.
 
Plec said:
The only other ideas i have will have crossed your mind and will have been dismissed as some are annoyingly time consuming and others dependent on having spare components to hand.

But:
  • re-seating CPU (especially looking at potential warping from heatsink around socket with such a small form factor) - small chance this could be the problem.
  • Spare PSU (if you haven't already) - can almost hear the audible groan from here if it means stripping yours :/
  • I'll end with a couple of easy ones (but i bet you've tried some already) - different stick of memory.
  • different HDMI cable - or even the dvi or DP
  • Last one is the kettle lead - try another.
Grasping at straws really, but the re-seat is annoyingly valid, but realise it will probably end up proving what you already suspect if you did it (vindication is always satisfying if not time consuming). Different PSU is always a possibility, as you know, but only suggested it as it's not mentioned - and a bugger if you haven't got one spare.

Hope you manage to salvage some of your Sunday - at least the beer will be cold by the time you get to it.
Click to expand...

I asked for it. Helping out someone. The masochist in me wanted to have a go at it.

Thanks for further ideas (different PSU already tested, reseating CPU was on my to-do list, different memory different slots can try as well cheers, tried two HDMi cables but will see if I can try different format).

I've pretty much discounted the PSU or lead as being faulty, to be honest. Won't close my mind to it though. Ever since adding the new battery, both PSUs run the fans fine and system stays on, just no post/display.
 
@Frederick Brinkley - i would start a new thread with your problem in the Water Cooling Forum (Click here). Then click on the 'Post New Thread' in the upper right of the screen. Give your thread a title in the first text box (e.g.Custom water cooled PS4 running hot.). Then give a detailed description of kit used and how it's setup and temps etc in the text box below and submit.
 
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