Desktop no longer booting

I’m dealing with some pretty severe system hangs that have now evolved into a total boot failure. It started over the weekend with a few hangs, two during heavy loads and one at idle. After the second reboot, I got stuck at the LUKS decryption step. Checking the systemd logs (via Esc) showed the below:

CPU#5 Utilization every 4000ms during lockup:
#1: 100% system, 0% softirq, 0% hardirq, 0% idle
...
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 23-....: (240005 ticks this GP) idle=....

I tried to boot a live ISO (Fedora 44 and Ubuntu LTS), but no luck getting those to work. The system just hangs after hitting “Install”.

As of today I can’t even get my main system to the point of allowing me to enter the LUKS key. It just freezes/hangs when I select which image of bluefin to boot.

Contacted support, but hoping there may be some answers from the community too.

I’d run some basic checks: explore the BIOS to see if it is stable, and if that’s OK, run memtest86 from a USB stick.

Oh yes, and use the BIOS to check the system time - if this is wrong then Ubuntu can fail to boot.

BIOs seems fine, I can change settings etc. Memtest86+ passed as well.

I am able to boot into my OS again, and boot live ISOs. So going to stress test the CPU/GPU to see if I encounter those hangs again.