Question Transported build won't display BIOS, stuck at A2 error

[tfburns]

Problem:
A2 code motherboard error, with no display output or BIOS screen showing. Although, I did get to the motherboard screen once, when I first encountered the A2 error and took out the Hard Drive and still had the M.2, GPU (using one of the HDMI outputs), and peripherals plugged in (have not been able to get a repeat of this behaviour).

Edit: I am now getting A2 on the mobo basic LCD + A2/CMOS error on the advanced LCD.
Edit 2: CMOS error gone after reseating the button battery. A2 error remains.

Context:
I recently transported a self-build PC. It was running fine before transport. Unfortunately the side panel (made of tempered glass) shattered during shipping and to clean out all the glass I had to remove most components. After rebuilding I encountered the A2 code error.

What I've tried:
1. Removing the M.2 and Hard Drive.
2. Unplugging/replugging GPU and other fans.
3. CMOS/BIOS reset by removing the motherboard button battery for ~10min with all peripherals disconnected and power off.
4. Removing all RAM (I then get a memory error code) and then booting with just 1 stick (I then return to passing the memory checks and getting the A2 code, followed by "post error").
5. Removing GPU and using on-board Display Port output.
6. Removing front panel motherboard connectors/USB connectors.
EDIT: Additional things I've tried:
7. Resetting BIOS to PRIME X299-DELUXE II BIOS 3801. A2 code error remains.

Question:
What should I try next? Unfortunately I don't have access to other components to swap in/out (other than new RAM sticks).

Hardware:
be quiet! Silent Base 801 Inverted Layout
Corsair Vengeance LPX 32GB DDR4-3200
Seagate Internal Hard Drive 12TB
Gigabyte AORUS GeForce RTX 2080 Ti Extreme Waterforce 11G
Asus Rog Thor 1200 PSU
ASUS All-in-One Water Cooling Unit CPU
ASUS Prime X299-DELUXE II
Intel Core i9-9980XE Extreme Edition 18 Core 3.0GHz
Samsung 970 EVO NVMe Series 2TB M.2

Motherboard manual:

PRIME X299-DELUXE II｜Motherboards｜ASUS USA

www.asus.com

 

[Lutfij]

Welcome to the forums, newcomer!

Edit 2: CMOS error gone after reseating the button battery. A2 error remains.
You might want to see if replacing the battery with a fresh cell helps.

Corsair Vengeance LPX 32GB DDR4-3200
Got a link to this ram kit? Which slots are the rams populating on the motherboard?

Resetting BIOS to PRIME X299-DELUXE II BIOS 3801. A2 code error remains.
Can you elaborate how you did this?

Removing GPU and using on-board Display Port output.
This is moot, the processor doesn't have an iGPU.

What should I try next? Unfortunately I don't have access to other components to swap in/out (other than new RAM sticks).
Troubleshooting is a process of elimination, which means dropping known working parts onto your system or a donor system that gets your system's parts to rule out which component might be the culprit, as opposed to pointing a finger at a part and hoping it's the right guess.

 

[tfburns]

Welcome to the forums, newcomer!

Thank you! And thanks for your kind reply

Edit 2: CMOS error gone after reseating the button battery. A2 error remains.
You might want to see if replacing the battery with a fresh cell helps.

Right, okay. Will add this to the list to try.

Corsair Vengeance LPX 32GB DDR4-3200
Got a link to this ram kit? Which slots are the rams populating on the motherboard?

This is the Amazon product page: https://www.amazon.co.jp/CORSAIR-メモリモジュール-VENGEANCE-16GB×2枚キット-CMK32GX4M2B3200C16/dp/B016ORTNI2/?th=1

I believe this is the official Cosair product link: https://www.corsair.com/us/en/p/mem...00mhz-c16-memory-kit-black-cmk32gx4m2e3200c16

EDIT: Apologies, forgot to mention how the RAM is currently installed -- currently I have just 1 stick in "DIMM_C1*", as suggested by the mobo manual for 1 stick.

Resetting BIOS to PRIME X299-DELUXE II BIOS 3801. A2 code error remains.
Can you elaborate how you did this?

I downloaded the new BIOS version and put onto a USB stick with the correct file name. While off, I plugged that USB into the designated USB slot. While powered but not on, I pressed the "BIOS_FLBK" button for ~3 seconds, until an adjacent green light started flashing. I let go of the button. After the green light stopped flashing, I pressed the power button of the computer. It turned on, got pass some CPU codes and reset on its own, did the same again to VGA codes and reset its own, and finally got through to the same HDD A2 error and hanged there.

Removing GPU and using on-board Display Port output.
This is moot, the processor doesn't have an iGPU.

Oh! So I guess I should put the GPU back in and see what it displays, e.g., does it show any BIOS stuff? I wonder if HDMI or Display Port is preferred? I guess DP?

EDIT 2: I installed the GPU and plugged my monitor into one of the DP outputs. The screen turned on and showed something quickly, then switched to text saying to not turn off the PC as the BIOS is updating. The PC reset automatically once but didn't show anything on the second (or subsequent) boot cycles, again hanging at the A2 error mobo code.

EDIT 3: With GPU in, monitor connected to a DP output, and 1 stick of RAM in slot C1, I stuck an Ubuntu USB in the rear I/O (direct mobo connection) and held/tapped "DELETE" or "F2" on my keyboard when powering on. The screen showed this:

I then pressed F1 to enter the BIOS. It seemed to work normally -- display was without errors, and keyboard/mouse responsive. I clicked "enter boot menu" and clicked what I thought was the USB. The PC restarted and then showed the same screen as above. I tried to find where to change the CPU fan, but couldn't quite work that out. I did run the automatic fan setting detector check, which took ~2min and then accepted some suggested fan speed changes. CPU temp was constantly around 30 degrees C and the AIO speed was around 2800. All case and AIO cooling fans were spinning. I clicked into the boot menu again, and this time chose a different option and it booted the Ubuntu USB. Display and keyboard/mouse worked fine.

I then chose to power down, as the Ubuntu live was not fully loading the desktop and I thought probably it is the slowness of the USB and/or the fact I only had 1 RAM stick on the mobo. I installed the rest of the ram and decided to reconnect the M.2 and HDD also, thinking I could see if they show up in BIOS. However, when I restarted I couldn't enter BIOS (issue as originally described: black screen and hanging on A2, with no way to enter BIOS). I disconnected M.2 and HDD, and extra RAM sticks, and the issue persists/can't get back to BIOS screen.

What should I try next? Unfortunately I don't have access to other components to swap in/out (other than new RAM sticks).
Troubleshooting is a process of elimination, which means dropping known working parts onto your system or a donor system that gets your system's parts to rule out which component might be the culprit, as opposed to pointing a finger at a part and hoping it's the right guess.

Right. I hope I can manage this with what I have access to. In the worst case, I will probably have to take it to a PC repair place, since I am in a new city and don't know anyone else yet.

 

[tfburns]

UPDATE: Someone lent me a working SSD to try. A2 error remained. The same person might be able to lend me 3.5" HDD to USB and M.2 to USB adapters, which will enable me to test if the drives work. At this stage I suspect that they do and that there is either a problem with the mobo or in the way I have set it up. If it helps, I can post photos of the current connections/etc. on the mobo.

UPDATE 2: I tested the M.2 using an SSK SSD enclosure (model SHE-C325). The M.2 loaded up fine and files were accessible. I tried to test the Hard Drive using an Inateck UA2001 device which claims to allow mounting via USB. However, this did not quite work for me. It could be the device or HDD. Either way, the M.2 is now known to work and HDD maybe or maybe not. This suggests it's a motherboard issue. But, then, did work a few times when updating BIOS, so hard to know the source of the mobo problem.