Question PC shutting down periodically, CMOS fail error

AndyTheDrifter

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Apr 24, 2012
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Starting a couple of weeks ago, every 1-3 days, my PC randomly shuts off, turns itself back on a few moments later, I get a CMOS fail error in the BIOS, I load the default settings, things work perfectly for 1-3 days until it happens again. I did some research and learned that repeated CMOS failures might mean my motherboard battery is dead/dying, but the problem persists even after replacing it with a brand new one.

I don't know if the CMOS fail error is the cause of the problem or a symptom. This PC is almost 7.5 years old so I know it's probably time to get a new one, but I'd like to hang on a little longer if I can. Anyone have any advice?

My specs:
-BIOSTAR TZ77XE3 motherboard
-Intel i5-2500k+ (at stock speed I think, I may have OCed it very modestly several years ago, but since I set everything in my BIOS to default, I think that it's gone)
-Radeon 7970
-8 GB RAM
-Crucial M4 128gb SSD
-Windows 7
-Don't remember my PSU but I can look it up if need be
 
It "need be", so just look at the PSU, no need to look it up. Should be right directly on the unit. Specifications decal is normally visible as soon as you take the side panel off, but occasionally, on cheaper units you may have to unbolt it and flip it around. Or, look it up.

Also, how long has it been in service?

Given the probable age of the unit this could be a PSU failure, but could just as easily, and highly likely, be a motherboard as well. Either are equally possible at this point.
 
Much as I hate to say it, even for a Seasonic unit 7 years is a pretty long stretch. I think that PSU needs to be replaced even if it's not the problem, and there's a good chance it is. While that was a really good unit back in the day, it looks very pale by comparison to todays power supplies.

Testing it would help determine whether it actually is the problem but again, I think that unit has seen all of it's useful life pass by already anyhow and likely, for the continued safety of your hardware, needs to be replaced anyhow.

Although, I have a feeling this is a board issue, it could still go either way. Maybe time to just upgrade the whole platform? Going to be hard to find a trustworthy replacement board worth spending money on since the last of those compatible boards was likely manufactured at least six years ago. Used models are likely not far from being in the same condition and new old stock will be ridiculously expensive compared to a new board for a current platform.
 

AndyTheDrifter

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Thank you for your help. I realize I might just need to bite the bullet and build a new PC and will do so if necessary, but part of me is wondering if I could just try to buy a new PSU. If that works, great. If it doesn't and the mobo is the problem, I can use the new PSU as part of a new build. But of course, for that plan to be viable a PSU would have to be both compatible with this ancient thing and good enough for a new PC.

I was looking at this Corsair RM750x, which seems to be popular and recommended for current builds. Would this be compatible with my current motherboard and case? Would that be a smart idea or am I trying to be too clever here?
 
Here's the thing, you can't lose either way if you get a PSU. If you build a new system, you needed one anyhow. If you get one and it fixes your problem, not only is your problem fixed but you already have one of the components you'll need whenever you DO decide to pull the trigger on a new build. I suspect it won't be long either way before you need to do that because we are beginning to see most of those Sandy bridge motherboards take a dirt nap due to the amount of time they've been in service.

The CPUs tend to last practically indefinitely so long as they are not abused, but the motherboard definitely has a service life because the capacitors and some of the other circuitry will only last so long even on a very high quality board, which that was not. I'm actually pretty surprised that Biostar board has lasted this long to be honest.
 

AndyTheDrifter

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Apr 24, 2012
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Yeah, this was my first PC build, and I went cheap on some of the seemingly less important parts like the motherboard and case. Lesson learned, lol.

But I'm a total ignoramus and haven't really followed PC hardware developments in seven years. As I asked in my previous post, will this new Corsair PSU that I'm eyeing (Corsair RM750X) be compatible with my current build (here's my current PSU (Seasonic M12II EVO 620 SS-620GM2 620W) and my current motherboard (Biostar TZ77XE3)? Both PSUs are ATX, is that all I need to know? I might end up just getting a new build regardless given that I'm going to have to shell out for Windows 10 in six months anyway given that support for Windows 7 is ending. But it would help tremendously if I have something to help me get by with my current machine til the new AMD Ryzen CPUs and Nvidia Super refresh cards are out and widely available in the coming weeks/months.
 
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And, it's a pretty good unit as well.

Also, you DON'T have to shell out for Windows 10 in six months. You can upgrade to Windows 10 now, for free, and then attach it to a Microsoft account in your name so that when you do upgrade you can simply move the digital entitlement to the new PC and not have to buy another license unless you plan to continue using the Windows 7 or upgraded Windows 10 digital entitlement on the current PC. If so, then you'd need to buy another one, if not, then you don't. But you don't want to wait until then to do it, because the free upgrade was SUPPOSED to have ended a long time ago, but so far has not.

Theoretically that is because they have wanted to continue giving the Windows 7 holdouts continued opportunities to move off 7 to 10 but once official support ends, or maybe even when it starts getting close, it's pretty likely they'll kill off the free upgrade because they'll have little reason to continue to allow it and not get paid for the use of it.



You will want to thoroughly read these as well.



And then follow my guide when you are ready to go IF you decide to do a clean install, which is advisable but not mandatory if you don't build a new system. If you do, you need to do a clean install if you want to avoid issues.