Question Asus X99-E WS Q-Code 91

[gru99]

I hadn't used my PC for a while, then it stopped booting. The LED tells me it stops on Q-Code 91.
I've tried:

• BIOS update
• removing all but one graphics cards (and trying them each at a time)
• removing all but one RAM

It still gives me Q-Code 91 and shuts down.

After replacing the board with a new one (and getting some new Nvidia cards as well) and reassembling the bare essentials, I'm again greeted with a Q-Code 91.

What else could cause the error?

 

[Darkbreeze]

Probably a dead CMOS battery. I'd replace the CMOS battery and then try again.

You can try simply resetting the CMOS as well if it's been unplugged for a while.

Power off the unit, switch the PSU off and unplug the PSU cord from either the wall or the power supply.

Remove the motherboard CMOS battery for five minutes. During that five minutes, press the power button on the case for 30 seconds. After the five minutes is up, reinstall the CMOS battery making sure to insert it with the correct side up just as it came out.

Now, plug the power supply cable back in, switch the PSU back on and power up the system. It should display the POST screen and the options to enter CMOS/BIOS setup. Enter the bios setup program and reconfigure the boot settings for either the Windows boot manager or for legacy systems, the drive your OS is installed on if necessary.

Save settings and exit. If the system will POST and boot then you can move forward from there including going back into the bios and configuring any other custom settings you may need to configure such as Memory XMP profile settings, custom fan profile settings or other specific settings you may have previously had configured that were wiped out by resetting the CMOS.

 

[gru99]

Thanks, yeah. That could be the idea for the old board. But the new one should have come with a fresh battery, don't you think? I'll give it a try though.

 

[Darkbreeze]

Sorry man, I didn't see that you bought a new one. My bad.

Even so, that's an old platform and it hasn't been manufactured for a long time. So any board that is X99 could definitely be in need of a new CMOS battery if it has never been replaced.

Have you tried using NO graphics cards, if the CPU model has an iGPU?

What are the FULL hardware specs for this system?

 

[gru99]

Motherboard
1* Asus X99-E WS/3.1

CPU
1* Intel i7 6900K

GPU
2* EVGA11GB D5X GTX 1080 Ti SC2 Gaming
2* water-cooled EVGA Hybrid 1080 Ti
Also tried it with 1 GiBy11GB D6 RTX 2080 Ti Turbo (as well as every card in a singular setup)

RAM
2* 8 GB DDR4-2666
4* 16 GB DDR4-2666
Also tried it with a single chip

Case
1* Thermaltake Core W200

HDD
2* SSD Samsung 500GB EVO

Power
Corsair AX1500i

 

[gru99]

Tried it with new batteries: same result. Q-Code 91. VGA_LED is lit. PC shuts down.

 

[Darkbreeze]

How old is that AX1500i?

 

[gru99]

About two years. Self-test looks okay (don't know if you can trust that). I've ordered a beeper and a few test kits, hopefully, I can narrow it down before having components for three PCs.

 

[Darkbreeze]

My biggest problem in trying to point you in the right direction is that Q-code 91 is almost non-existent aside from about three threads in Google results. There is no bulk of samples to try and look at what seems consistent with your problems, based on what has been done historically for similar code elsewhere. Other codes have PAGES of results. Seems, unusual.

 

[gru99]

Yeah, that's what's puzzling me as well. If I get more data, I'll post it tomorrow. It's probably a stupid mistake on my side.

 

[Darkbreeze]

Seriously, I would tear the whole thing down, test with a single CPU and double check that there are no bent pins and that you've connected ALL the required connectors such as the EPS and ATX power cables FULLY seated, etc, etc. It's really easy to have done something wrong, although, the fact that this system worked (It DID didn't it) prior to sitting for while is puzzling.

How To - Motherboard bench testing

Finding the problem through bench testing If you are here then it’s likely you have encountered a serious hardware issue and have been unable to resolve it using the standard no-POST troubleshooting procedures. If you have not yet attempted to resolve your issues using the no-POST...

forums.tomshardware.com

Is the new motherboard model the same as the old motherboard model, and did you buy it new or used?

WHERE was this being stored while it was not in use, and was it connected to power and just not in use or was it fully unplugged and stashed somewhere? Basement? Damp area? Humidity? Anything that might have created corrosion somewhere?

 

[gru99]

It has worked before. For, let's say, about 22 months it ran successfully. A setup with four GPUs (two watercooled, two not) maybe unusual and the heat was somewhat intimidating, but it did its job. It had been off for two months (moving), but after powering up, everything looked fine, the second startup failed. And since then I haven't been able to get it running. I had checked that nothing was disconnected before starting the system.
As for corrosion: the mainboard is new, the GPUs are new (at least the ones I've used for tests). I've switched a few RAM chips (though not new ones). The only things I haven't changed is the CPU (I'll check the pins) and the Corsair. And humidity? Never say never, but I've been in the same room as the PC. Doubt it.
The new motherboard is an Asus X99-E WS/without 3.1. Question is: what's the important Q-Code? The one you see last (and for a long time) or the one when the VGA LED lights up? Then it's probably Q-Code 61 (for a split second only). But googling for this didn't help either.

 

[Darkbreeze]

The Q code it either hangs on or restarts on, is generally the important one. There are a variety of codes shown during a normal POST process and none of them matter so long as it doesn't cause the system to stop.

The only two components, that I can see, which are the same from attempt to the next factoring in changes of hardware are the CPU and power supply, so those would be the main culprits I think.

It would be EXTREMELY doubtful for several graphics cards, multiple sticks of memory (Be sure to test with a variety of single sticks from both sets), two different motherboards, etc.

For the sake of being thorough, make sure to disconnect ALL storage devices and USB parts aside from the keyboard and mouse, and try to POST. I've seen bad drives and other USB devices cause issues before.

I see no mention of CPU cooler? What CPU cooler are you using?

 

[gru99]

Thanks. I'll check that.

CPU cooler: Noctua NH-D9L.

 

[Darkbreeze]

Is the fan on that unit spinning when you power on? Does it STAY spinning until the system shuts down?

How exactly does the system shut down? Does it seem like it goes through a shut down process or does it just suddenly power off?

 

[gru99]

The fans are spinning up to Q Code 91. Then all the GPU fans stop. I'm not sure about the CPU ones.

The process is: it quite quickly goes through all the stages, then the VGA LED goes up, it still switches through a few codes to the ultimate 91. It takes about 30 seconds on 91 before the system shuts down (without restarting).

 

[Darkbreeze]

Check the CPU cooler. If the fan has failed or is failing, and the motherboard does not receive an adequate RPM signal, it will automatically shut the system off to prevent overheating UNLESS you have disabled that feature in the bios. The only time anybody would want to do that is on a system using a passive heatsink with no fan like the giant Silverstone Heligon or something similar.

For all other systems, no RPM signal from the CPU_FAN header will do exactly what you are seeing happen, although usually faster than what you are seeing. Worth checking though. Maybe the fan is working when first started but then poops out and triggers a shut down. IDK, I'm reaching here.