Question Occasional Critical Stop Event ID 41, PSU and UPS

BonzaiDuck

Lifer
Jun 30, 2004
15,708
1,450
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The system in my sig was the most perfect PC I ever built, put together during late 2016 -- refinements through spring 2017. It was all part of a plan, and for four years, it was absolutely stand-up marvelous and perfect -- performing as I'd anticipated when I planned. The processor and chipset (Z170) are five-year-old -- perhaps six-year-old technology. And of course, for a Skylake K processor, part of the plan was to overclock it. And no problem with that, either: the processor received Silicon-Lottery's de-lidding and re-lid with Conducto-naut TIM.

Just over a year ago, I had an accident with a static charge and a vaping-pen thoughtlessly placed in a USB port. I replaced the motherboard with the identical model, and just decided to replace the Skylake with a Kaby Lake i7-7700K processor -- a whim. I also replaced my RAM with a 2x16 G.SKILL TridentZ kit -- also stellar, also unnecessary.

Everything was back up and running by around April, 2021, with the Kaby Lake OC'd and tested for a modest 4.8Ghz turbo speed. No problems. Then, in July, the system wouldn't post at boot-time, and I just set it aside for about three months or so, weary of trouble-shooting. It turned out that I'd left a software-install CD in the optical drive, and the system was stalling during drive enumeration, appearing to have some boot failure. I even decided to replace the Seasonic Titanium PSU, but it was unnecessary, and I remember when it dawned on me what I'd done that summer with the install CD. I opened the optical drive and removed the disc, then "Voila!" -- everything back to normal.

But every so often, first -- once monthly with a randomly varying interim of time -- the system would reset itself, showing Event ID 41 -- critical stop due to power event. It wouldn't even leave a mini-dump file to analyze. I watched it. By January, 2022, it was happening about once every two weeks. I'm not a naive mainstreamer, buying my systems at COSTCO and contracting with Geek Squad or whomever to service them. My attention was focused on these crashes and shutdowns that occurred with Event ID 41.

I began to suspect the new PSU. But then, I opened the Event Viewer after writing down the detailed codes of the last Event ID 41, tracing them back to when I first THOUGHT they had occurred, or after I resurrected the system with a new PSU. I discovered that identical event-log shutdown errors had occurred in late June, or about two weeks before I inserted the non-bootable CD that was causing the system failure to post. This occurred BEFORE the PSU swap-out.

I was also refurbishing and replacing my UPS battery backup units around the house as needed, and had purchased the replacement for the old unit used for my Skylake system. I didn't get around to deploying the new UPS over the entire time I was concerned about the critical stops. But finally, I swapped in the new one last week. I had found thread posts and forums in which the details of critical stop Event ID 41's were discussed with the same identifying details as mine. Advice suggested that the culprit was either a PSU or a battery (on a laptop).

I suspect that replacing my UPS may have solved the problem, but I won't confirm it myself until the system has run at least a month without further problem. Oh -- and BY THE WAY -- while fretting over this problem, I had set all the OC settings back to "optimal defaults" and even decreased the RAM speed setting from 3200 to 3100. So OVERCLOCKS DIDN'T FIGURE into these random shutdowns.

UPS devices have a switching assembly that reverts to battery when AC power falls below a preset threshold. I suspect that this part of the UPS was failing, interrupting power to the PSU, and causing the shutdowns.

While I wait to verify this, does this seem like a feasible explanation to any other members? Do any other members have experience with a UPS failure similar to the one I suspect? Does my diagnosis sound correct? There are additional minor symptoms which have disappeared since I replaced my UPS.
 
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BonzaiDuck

Lifer
Jun 30, 2004
15,708
1,450
126
Again -- I see no responses on this. Perhaps my OP's are TLTR. But nobody else has an opinion.

I swapped out the UPS two weeks ago. The same sort of crash "Critical Stop Event ID 41" occurred again.

Sometimes, these crashes, about every two weeks, are concerning. In order to get the PC to cold-boot, I have to unplug and turn off the PSU, then plug it back in and turn it on.

I ran the Intel CPU Diagnostic on the Kaby Lake 7700K, and it checks out. So I'm reviewing what got changed, besides the motherboard, after my January-2021 USB "vaping pen and static charge" accident.

I swapped in the Kaby Lake for the 6700K Skylake.

I swapped in a 2x16 32GB TridentZ RAM kit, replacing a 4x8 configuration.

I swapped in a new, identical Gigabyte Mini OC GTX 1070 card.

The intention was to simply build a twin system using the spare parts. I'll be criticized for not keeping up with the "latest and greatest", but there are a lot of tech-veterans I know who make good use of dated technology, and I"m not ready for a hexa/octo/deca-core processor and board. I simply don't need the extra power now.

Some web-forums and their threads suggest a RAM problem, and this is significant.

Here's the story. I was looking for a 2x16 kit, actually hoping I could run them with the command-rate set to 1. But that won't work with the TRIDENTZ GTZR pair I bought. [and -- Oh, wonderful! -- the sticks have LED lights].

Of course I tested these initially. However, they were never advertised to work specifically with the Z170 chipset, but rather for the Z290 or the succeeding generation. Since I never found validation for them with the G.SKILL "configurator", I sent e-mail to G.SKILL. Usually, I can rely entirely on their responses, but this one was tell-tale: they said "Oh -- the GTZR's will PROBABLY work OK, but not necessarily at their spec speed. You can try . . . "

I suspect a RAM problem with these Critical Stops every couple weeks. I think I'm going to swap in my 2x8 TridentZ GTZ kit or kits to test. Apparently, for $120, I can get a pair of 2x16 RipJaws which are specifically identified as compatible and acceptable for the Z170 chipset.

Again, any insight about this would be appreciated. I'm reasonably sure now that the occasional power events are not due to the UPS, the PSU or the processor. I cannot see how the motherboard would have some defect that would cause the power events so infrequently -- but if push comes to shove, I have a spare brand-new from an ASUS RMA, of the identical model. So far, there has been no disk or file corruption, and these events only seem to occur when the system is at idle -- not being used.
 

BonzaiDuck

Lifer
Jun 30, 2004
15,708
1,450
126
No need anymore for response to this thread. My problem is likely not the PSU, and not the UPS. Other recent threads point elsewhere . . .
 

BonzaiDuck

Lifer
Jun 30, 2004
15,708
1,450
126
I was going to say, might be your mobo. Or maybe CPU.
I still worry about those items, Larry. Some other forum threads elsewhere seem to suggest it could be RAM first of all.

I ran the Intel Processor diagnostic tool on the CPU, but it throws all green checkmark "pass" results for everything.

The motherboard can be replaced, but it will be a tedious project, given all the other s*** I'm doing daily. I had purchased this current one as an open box, verified and tested as OK in every respect. I couldn't find anything wrong with it. I didn't NEED to purchase it; I could've waited for the ASUS RMA return under the 5-year warranty. ASUS always sends flawless replacements, and that ASUS replacement is waiting for use in case I need it.

I just don't like pulling the whole PC apart, then re-activating Windows and other software. I'm hoping it's neither the processor or mobo.

I'll say this, and in regard to the other thread I started. The replacement GTZ RAM -- known good -- seems to be working fine, and as I'd said in that other thread, symptoms of power-starvation have disappeared (the grinding fan noises, for one.)

And also as I'd said in the more recent thread, there's nothing to do but wait and see. No critical stop crashes so far. But if they had been occurring sometimes as much as two weeks apart, I'll have to wait and see. Obviously if this were something that occurred twice daily, I'd be applying a different strategy for fixing it.