Motherboard failure or PSU failure?

[truepusk]

I think it's my motherboard/CPU, but it's hard to know for certain without swapping out every single other component, including the PSU. I don't have a PSU and I don't want to have to go get one, but it would be nice to be a little more sure than I am so that I can be comfortable reusing my PSU for my next build. Or is that a bad idea given that my PSU is more than 8.5 years old?

More specifically, my symptoms:

• BSOD or spontaneous restarts started a few days ago
• The computer has also had issues starting up. It will power up and then die before posting and relatively repeat that cycle in an automated fashion.
• It also started freezing up intermittently, in addition to the BSOD
• I didn't run memtest, but skeptical that it will use anything from continued posting issues after trying/swapping a reduced set of my memory modules
• Swapped out GPU, same results
• At one point in time after intermittent and repetitive automatic failed posting attempts I saw a message that it lost the bios image and recovered it from some backup set
• Note that I can eventually get my computer up and running again if I try to restart it enough, but it will eventually freeze up

Do these systems seem very likely to be motherboard related or is there a chance it's my PSU?

 

[UsandThem]

Trying to diagnose issues over the internet is tough. You could rule out the PSU by using a multi-meter to get the PSU's output at idle and load.

The other way is to buy / borrow one and find out that way. That said, what you describe sounds like the PSU is the most likely problem, so that's where I would start at first. You didn't say what model PSU you have, but 8 1/2 years is a long time for most PSUs (outside of the best built units). I would personally not move such an old PSU over to a new build (unless it was a really solid unit with all Japanese capacitors, was modern in terms of protections, etc).

But your full system specs would help.

 

[truepusk]

Here is my rough system specs, as of 8+ years ago when I built it. It's an i5 760.

• SeaSonic S12II 520 Bronze 520W
• I've since upgraded the above system w/ more RAM a few times, (currently running 4x4GB = 16GB as of 1 or 2 years ago)
• I've also upgrade the GPU to MSI Radeon RX 480 4GB 2.5 years ago

I'm surprised to hear you think it's a power supply issue. I guess a few thoughts and/or questions on that:

• I ran Open Hardware Monitor on it last night. For whatever reason it only seems to give the CPU and GPU core voltages but not display the 13 and 5V rails or anything else. I couldn't see anything of note.
• For whatever reason the intermittent and other characteristics of the symptoms lead me to motherboard and not PSU
  • So it is normal for the system to have heavy intermittent issues starting up but then to eventually start up when you are having PSU issues?
  • And then the thought is something that I'm doing EVENTUALLY causes the load to increase or just in general the voltage output dips?
• I'm inclined to think that trying to get multi meter leads in there to read voltage levels would be a huge pain, just from memory of trying to do similar things in the past. Don't they normally do a pretty good job of insulating the connectors so that there is no bare metal to read? Hmmm.... maybe not... I'm going to run off now and look for some ATX pinouts.

Note, I'm heavily swayed by you to not reuse the PSU on a replacement build.

 

[truepusk]

Okay, I can totally check these voltage levels...
This pinout looks good - http://powersupply33.com/atx-power-supply-pinout.html/atx-power-supply-pinout
There looks to be space to jam leads in behind the ATX connector
And, as far as figuring out how many buses there are to check, I think this info from here (SeaSonic S12II 520 Bronze 520W)will be helpful:

• +3.3V@24A, +5V@24A, +12V1@20A, +12V2@20A, -12V@0.8A, +5VSB@2.5A

What I'm not sure about at this point (need more research or more input from you all... ) is where 12V2 goes? Looks like maybe 12V1 but is the only 12V that goes straight to the motherboard so maybe 12V2 is for peripherals, but not sure. Looks like all the other buses go straight through the ATX connector.

 

[esquared]

Maybe this is naive but what about buying a PS tester?
I have used a couple before and they did in fact , diagnose
a bad power supply.
I had one similar to this:
https://www.amazon.com/4-pin-Power-...y+tester&qid=1557007045&s=electronics&sr=1-28

and I now have an Antec tester.
https://www.newegg.com/Product/Product.aspx?Item=N82E16899129002

 

[truepusk]

I'm guessing 12V2 is the second connector (separate from the ATX) that goes to the motherboard closer to the CPU. Looks like it's 8 pin.

 

[truepusk]

I think my power supply is okay (not saying I'm going to reuse it).
I figured out how to use this Open Hardware Monitor app a bit better. I can enable hidden voltages and log them. The voltages generally seem pretty stable except for the CPUVCore. I can make it drop quite a bit by increasing or spiking the PC load.

The application logs some of the incoming voltages from the power supply (3.3, 5) but not all (12, -12). But from looking at the multimeter I don't see much variation in those others.

I do see the 5V occasionally get as low as 5.00 V on Open Hardware Monitor, which I don't love, but I think the CPUVCore is generated from 3.3V, regardless (at least that would be my guess). 3.3V is rock solid.

And btw, throughout this monitoring I was getting occasional BSOD/reboots. They aren't necessarily correlating with CPU load that tightly - tough to tell.

So I think there are some issues with the motherboard. Maybe a blown cap on the CPU voltage line or something similar. I'd be interested in other opinions based on these observations.

 

[RLGL]

8 years old, do not waste time or effort. Start over, upgrade.

 

[VirtualLarry]

8 years old, do not waste time or effort. Start over, upgrade.

I know, seriously, right? What is OP going to do, get another (used, 8-year-old) mobo that's working, only to have it fail one year later again? Or what if it's the CPU, if it just got "tired"?

Ryzen's cheap and cheerful. Jump right in. 1st-Gen Ryzen CPUs (at least the R5 1600) have hit fire-sale prices. I picked up several recently for builds for friends and family.

Edit: I guess, in the grand scheme of things, an "old used board" might be worth it, if it can be had for under $50, or preferably, under $30, but most older boards for obsolete sockets, that are still in use, are sky-high pricewise on the second-hand market if they're in good shape. Look at 1150 ATX boards. 1156 boards were kind of rare, too, because many of those boards had known socket problems, that would result in scorch marks on the CPU. (Look for "LOTES" sockets on the board. "Foxconn" were the ones that were reported to be problematic back in those days, IIRC.)

 

[truepusk]

I know, seriously, right? What is OP going to do, get another (used, 8-year-old) mobo that's working, only to have it fail one year later again? Or what if it's the CPU, if it just got "tired"?

8 years old, do not waste time or effort. Start over, upgrade.

After getting the advice that saving the PSU isn't worth it even if it's good, the only remaining calculus was just replacing the PSU in the off chance that it was the only bad component. At a minimum it would've been awesome to get it up and running quickly while I figure out new components and at a maximum I decide to keep on truckin' with what I've got.

EDIT: In other words, I'd only consider saving the system if only the PSU was bad.

 

[VirtualLarry]

Oh, yeah, that makes sense. Try another fresh or at least known-working PSU first, maybe a CMOS battery replacement (check your local dollar stores). If that doesn't work, THEN junk it. Sorry.

 

[truepusk]

maybe a CMOS battery replacement (check your local dollar stores).

Good thinking, it was worth a shot despite the Open Hardware Monitor app claiming battery voltage was fine. I'm a DIY EE, so I've got a component drawer full of them, but no dice. I did hear from the sage, Continuum on Ars, that PSUs are pretty affordable these days but I don't have anything on order yet.