Ubuntu 20.04 shuts down suddenly

My Ubuntu 20.04 shuts down suddenly, without particular stress on the machine (just while surfing the internet).

From cat /var/log/kern.log | grep 'Error' around the last shutdown time:

May 23 10:07:18 hal9000 kernel: [  628.089083] mce: [Hardware Error]: Machine check events logged
May 23 10:07:18 hal9000 kernel: [  628.089086] [Hardware Error]: Corrected error, no action required.
May 23 10:07:18 hal9000 kernel: [  628.089090] [Hardware Error]: CPU:0 (17:71:0) MC25_STATUS[-|CE|MiscV|-|-|-|-|CECC|-|-|-]: 0x98004000003e0000
May 23 10:07:18 hal9000 kernel: [  628.089094] [Hardware Error]: IPID: 0x000100ff03830400
May 23 10:07:18 hal9000 kernel: [  628.089096] [Hardware Error]: Platform Security Processor Ext. Error Code: 62
May 23 10:07:18 hal9000 kernel: [  628.089097] [Hardware Error]: cache level: RESV, tx: INSN
May 23 10:08:55 hal9000 kernel: [    0.535518] RAS: Correctable Errors collector initialized.
May 23 10:19:17 hal9000 kernel: [  627.703179] mce: [Hardware Error]: Machine check events logged
May 23 10:19:17 hal9000 kernel: [  627.703182] [Hardware Error]: Corrected error, no action required.
May 23 10:19:17 hal9000 kernel: [  627.703187] [Hardware Error]: CPU:0 (17:71:0) MC25_STATUS[-|CE|MiscV|-|-|-|-|CECC|-|-|-]: 0x98004000003e0000
May 23 10:19:17 hal9000 kernel: [  627.703191] [Hardware Error]: IPID: 0x000100ff03830400
May 23 10:19:17 hal9000 kernel: [  627.703193] [Hardware Error]: Platform Security Processor Ext. Error Code: 62
May 23 10:19:17 hal9000 kernel: [  627.703195] [Hardware Error]: cache level: RESV, tx: INSN

My lscpu

Architecture:                    x86_64
CPU op-mode(s):                  32-bit, 64-bit
Byte Order:                      Little Endian
Address sizes:                   43 bits physical, 48 bits virtual
CPU(s):                          16
On-line CPU(s) list:             0-15
Thread(s) per core:              2
Core(s) per socket:              8
Socket(s):                       1
NUMA node(s):                    1
Vendor ID:                       AuthenticAMD
CPU family:                      23
Model:                           113
Model name:                      AMD Ryzen 7 3700X 8-Core Processor
Stepping:                        0
Frequency boost:                 enabled
CPU MHz:                         3349.889
CPU max MHz:                     5224,2178
CPU min MHz:                     2200,0000
BogoMIPS:                        7187.05
Virtualization:                  AMD-V
L1d cache:                       256 KiB
L1i cache:                       256 KiB
L2 cache:                        4 MiB
L3 cache:                        32 MiB

I am on NVIDIA GeForce RTX 2060 INNO3D.

Any Clue?

Thanks to the suggestions in comments, I came to the conclusion to reset my BIOS to default settings. It turned out that so far so good, no sudden reboots in the last 12 hours.

Probably was that.