AMD Ryzen 9 5950X Stability Issues on X370




Changing VSOC voltage to 1.0 and DRAM voltage to 1.35 solved the issue.


I’ve had some trouble with AMD processors for some time. I might have lost the silicon lottery twice in a row or there is something fishy with the combination of CPU, RAM, MB, and BIOS settings that I run. In 2020 I wrote the following in my Github Debian dotfile repo:

I have actually had Debian 10 crash a couple of times, with the error messages regarding the CPU. I do not know exactly what the error is, I have only heard that it has previously been problems with AMD Ryzen CPUs and some kernels. The reason why I did not have any problems on Ubuntu, I think, is beacuse I was running version 18, which ran a kernel where this bug wasn’t present.

At this point in time, I ran an AMD Ryzen 5 1600 with the Asus Prime X370-Pro motherboard. Before installing Debian on this machine I ran Ubuntu and I did not report any issues, however I’m unsure if I used the computer in the exact same way etc.

Furthermore, AMD Ryzen instability issues are widely known and for example discussed on the ArchWiki.

I’ve since then changed the memory and the CPU and the error still occurs at my current setup with the AMD Ryzen 9 5950X CPU.

Kernel crash dump

Installing kernel crash dump to investigate the issue.

sudo apt install linux-crashdump

Select yes to let kexec-tools handle reboots and yes such that kdump-tool is enabled by default. If you want to check that this is enables nvim /etc/default/kexec and look for LOAD_KEXEC=true and nvim /etc/default/kdump-tools and check for USE_KDUMP=1.

Now we need to reboot the machine. Afterwards, we can see the current status of kdump with kdump-config show,

DUMP_MODE:		kdump
KDUMP_COREDIR:		/var/crash
crashkernel addr: 0x
   /var/lib/kdump/vmlinuz: symbolic link to /boot/vmlinuz-6.2.0-33-generic
kdump initrd:
   /var/lib/kdump/initrd.img: symbolic link to /var/lib/kdump/initrd.img-6.2.0-33-generic
current state:    ready to kdump

kexec command:
  /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz...

This tells us that the core dumps will be found in /var/crash.

The Error

The computer runs smoothly without any issues when it’s idle or when I run heavy calculations. I have not turned off the computer since sometime during the spring, now it’s September, and I’ve not had any issues. However, when I run an Erigon Ethereum archive node (not maxing out the CPU) the computer freezes randomly from time to time. It can run for a day or a few days and then all of a sudden it freezes.

Restricting the CPU to only C-state 1 (Did not work)

Adding the processor.max_cstate=1, rcu_nocbs=0-11, and idle=nomwait parameters is a way to limit the CPU’s sleep states, help to off-load RCU callback processing, and prevent the kernel from executing the MWAIT instruction. This can sometimes improve system stability or performance for certain specific tasks.

To limit a CPU to a certain C-state, you can pass the processor.max_cstate=X option in the kernel line of /etc/default/grub. We can look at the current kernel parameters with cat /proc/cmdline. Now lets cd to /etc/default and sudo cp grub grub_backup. Then add the following to grub: GRUB_CMDLINE_LINUX_DEFAULT="quit splash processor.max_cstate=1 rcu_nocbs=0-11 idle=nomwait". Now we can updage grub with sudo updage-grub and reboot.

Now when we run cat /proc/cmdline,

BOOT_IMAGE=/boot/vmlinuz-6.2.0-33-generic root=UUID=dfae9aa3-c27e-4f1b-8535-94cac7dc19ba ro
quiet splash processor.max_cstate=1 rcu_nocbs=0-11 idle=nomwait vt.handoff=7

Here is a breakdown of what each parameter means:

Update BIOS

After updating the BIOS you can run sudo dmidecode -s bios-version to check the version. For me the command now gives 6203.

What have not solved the issue

Things to try

Increasing VSOC and DRAM voltages

It could also be an issue of the CPU getting too low of a voltage when clocking down. However technically, I’ve already tried to increase the VSOC voltage when overclocking without success. At this point in time my hypothesis is as follows: I think that the initial issue was with the CPU and that I fixed that, but that I also have a RAM issue.

The DRAM voltage is by default set to 1.2 voltage in the BIOS (for some reason?), I increased this to 1.35 (which is the Corsair recommended voltage). I also changed the VSOC voltage from 0.975 to 1 voltages (do not go higher than 1.1). For my motherboard these settings are changed in the BIOS, entering the advanced mode and then Ai tweaker.


In the end, after increasing the VSOC voltage to 1.0 and the DRAM voltage to 1.35 I had no more crashes.