Asus Maximus XI will not boot with 3080 plugged in post bios update

smegle · 1 Jan 2022 at 05:35

Hi all,
Flashed my bios on my Maximus Xi this morning and it wouldn’t post initially. I then noticed I’d stupidly used a usb stick that still had some other hidden files on to flash the bios. It said it was complete but then repeatedly wouldn’t post.
Had a variety of errors from 97 and 92 then a2 and a0.
I then reflashed to a previous bios (that I’d not used either as the one I was running was old) using the usb and the bios button on the back.
I could get it to boot using the hdmi on the board but not on my 3080. Just gives me code 92.
If I unplug the hdmi, boot under windows on the onboard graphics, then plug in my reverb g1 hdmi it works absolutely fine. In game is fine also.

could there be a setting I’m missing or could there be something more terminal with the board that could put risk to my 3080?

many help is appreciated and happy new year!!

VersionMonkey · 1 Jan 2022 at 11:40

Have you cleared the CMOS and then gone into the BIOS to load optimised defaults?

smegle · 3 Jan 2022 at 06:50

Hi - yes done all this and even reflashed the bios.
I can get it all to post fine if I put the mono in uefi comparability mode. It shows just the 3080 and runs benchmarks well too.

if I turn off uefi compatibility it again won’t post the bios and hangs.

The card is running 3marktimespy, raytracing benchmark all fine and I’ve even had them looping for half hour with good temps.

min dcs however I can only get approx 10 mins of play before dcs crashes (in fps vr the cpu frametime is still working hard but the gpu load and frametime disappears and the headset is frozen)

Do you think these could be related and does anyone have any thoughts on the uefi comparability issue?
Thanks

Joxeon · 3 Jan 2022 at 09:52

Is Windows installed as MBR or GPT?

smegle · 4 Jan 2022 at 20:55

Joxeon said:
Is Windows installed as MBR or GPT?

gpt - which should it be?

VersionMonkey · 4 Jan 2022 at 22:24

smegle said:
gpt - which should it be?

If you want to boot in straight UEFI (which disabling CSM will force), then the disk will need to be using GPT - so that is correct.

Did you have CSM disabled before you did the BIOS upgrade? If I remember correctly, some people have had to update GPU firmware to boot with CSM disabled, but if it was working previously then it seems unlikely that is the problem.

smegle · 9 Jan 2022 at 11:05

VersionMonkey said:
If you want to boot in straight UEFI (which disabling CSM will force), then the disk will need to be using GPT - so that is correct.

Did you have CSM disabled before you did the BIOS upgrade? If I remember correctly, some people have had to update GPU firmware to boot with CSM disabled, but if it was working previously then it seems unlikely that is the problem.

Hi,
I’m pretty sure when windows was installed the bios was on stock settings as I’d never updated it or changed it since I installed windows.
I’m honestly not sure how I’d check back now tbh unless I did a full new install?

VersionMonkey · 9 Jan 2022 at 11:59

smegle said:
Hi,
I’m pretty sure when windows was installed the bios was on stock settings as I’d never updated it or changed it since I installed windows.
I’m honestly not sure how I’d check back now tbh unless I did a full new install?

No way of knowing, but it seems likely you did not disable CSM previously (it's typically enabled by default, so if you left the BIOS at stock before you did the update, then CSM would have been enabled before).

A quick google suggests that at least some 3080s have indeed needed a firmware update before CSM could be disabled. If you have no reason to disable it, then leave it on.