Asus Z690 Apex boot issues

[thebski]

Hey guys,

I've got some kind of demon in my PC I've been battling for a while now. When I power on the PC after successful shutdown, it fails to boot. It never reaches the "Press Del to enter setup" screen. It gets stuck on various boot codes. I've seen code 99, Ad, b6, etc. There doesn't seem to be any consistency to this. If I use the clear CMOS button on the back, it will boot fine, but of course I have to reset bios settings. Even changing no bios settings results in the same behavior. I boot into Windows, shut the machine down, and it will fail to boot on next attempt until I clear CMOS again.

This has been happening for a while. I had a 12900K in the Z690 Apex for almost a year. Yesterday, I installed my 13900K and moved the system to a full liquid cooling setup. I had hopes that this would solve the problem as it required the latest bios update for the CPU to work, I was using a block built for LGA 1700 (12900K only had an AIO with socket adapter kit). In my head I thought maybe the original AIO cooler wasn't mounting quite right and was putting too much pressure on the CPU to do the quick memory training.

The odd thing is, after my 12900K setup did this for so long, I move houses. After the move, it worked perfectly fine. Now that I took the components out of the old case and installed them in the 1000D and watercooled the CPU and GPU, it's doing it again. It's a very annoying issue, as you can imagine, since I have to reset any bios settings every time. I have custom fan curves controlling the pump and radiator fan speeds based on a water temp sensor, and I'd like to overclock, but I'm not even going to try until I get this issue sorted.

Has anyone ever seen anything like this? I've been building PCs for almost 15 years and this is a new one on me.

System Specs:

Asus Z690 Apex
Intel 13900K
32 GB Corsair DDR5 Memory
EVGA RTX 3080 Ti FTW
EVGA 1000 T2
2 TB Samsung 980 Pro and 1 TB Samsung 970 Pro on Dimm.2 stick

Any help is appreciated. I'm not really sure where to turn from here. I'm about down to trying a new board, but man they're $700 and there's not a thing wrong with this one once it boots. It seems to have something to do with the boot sequence after a CMOS reset vs one after normal operation, but I don't know anything about that.

Thanks guys.

[thebski]

After some testing I've seemed to narrow down what's causing the issue, now the question is how to solve it. It has something to do with having my second monitor plugged in. If I unplug the second monitor, it boots fine, over and over again. If I plug the second monitor in, it will boot once, and the next time it will not boot. I've tried both display ports that are available for the second monitor and the behavior is the same. This makes no sense to me at all. Any ideas?

[JohnAb]

Good that you are onto something. Faults like that are a nightmare. I have an idea - it might be a faulty monitor cable or plug. Try a different monitor in the same port. If still OK, you can start to troubleshoot the faulty monitor. If the fault sill exists, it might be a dodgy GPU socket. I had a faulty USB cable that caused me months of headaches. Good luck. If all else fails, call a Priest to sort out the demon lol

[JBBlack]

I have nearly the same exact setup (however I also have 6 SATA drives installed) but have never had this same issue.

However, after updating the BIOS to 2204 I did have one of my 4k monitors not come on at boot, even after logging into win 11, I would have to turn it on manually even though I never turned it off. BUT the strange thing was that windows recognized that monitor even though it was turned off (or still in sleep?) as it would arrange my icons on the monitor like it was on. (like not trying to use only one monitor)

I thought I had a bad monitor or cable so I changed the cable(s) and then I went through the BIOS thinking that after the update I must have missed a setting someplace and changed some settings, I can't for the life of me remember what I changed, but "something" stopped the issue and has never happened since.

Not the same issue I realize, but it might have something to do with the cable OR possibly something you're missing in the BIOS.

Note, both my 4k's are running through display ports on my FTW on heavy high-grade cables.


PS: the only other thing I have ever had that game me a Ghost in my machine, was a bad SATA cable, you would have thought the PC was possessed by demons....all for a bad cable (that was NEW when I used it)

[thebski]

It's a strange issue for sure. At this point after fiddling with a bunch of things, I don't think it's the motherboard, as that just doesn't make a lot of sense.

I'm running an EVGA RTX 3080 Ti FTW3, an Asus PG278Q at 144 hz 1440P and a Samsung Odyssey G8 at 240 Hz 4K. Both monitors are using the DP cables that came with them. I've tried each monitor individually by themselves in all ports and everything seems to boot fine. Right now, it's booting fine with the Odyssey plugged into DP1 and the Asus in DP2. I originally had the Asus in DP1 and couldn't get it to work with the Odyssey in DP2 or DP3. It makes no sense, but for now, it is working. I'm not sure if the GPU has something funky going on or what. At any rate, I'm not going to worry about it. I'll upgrade to a 4090 (or 4090 Ti) when I can eventually get my hands on a Founders card without laboring for it, so it will likely not be until they're well into their life cycle. As long as it keeps working, I'm not going to mess with it.

I also discovered that just unplugging the Odyssey and plugging it back into the GPU has the same effect as clearing the CMOS, so I've since overclocked the system and if it starts giving me fits again I will just have to unplug and plug in the monitor before boot. It would be really annoying, but I'm not sure what else to do.

[Silent_Scone]

Hello,

Ensure the VBIOS firmware is up to date if this has not been mentioned already.