Hi,

I’m experiencing random instant reboots on an Unraid server and I’m running out of things to rule out.

Hardware

• Ryzen 5 5600G (APU)

• Gigabyte B450 AORUS M

• BIOS updated recently (post-2023), Optimized Defaults

• 32 GB DDR4 (Memtest86+ = 0 errors)

• WD Blue SN570 NVMe

• No GPU, no VMs, no encoding

• Two different PSUs tested (including Corsair CX550) → same result

Symptoms

• Instant reboot, no freeze, no shutdown sequence

• Motherboard LEDs don’t even turn off

• Happens randomly (sometimes ~10 minutes)

• No logs at all, not even on a remote syslog server

• Only normal boot logs before the crash

What I’ve tried

• BIOS update + defaults

• Global C-States disabled

• iGPU enabled with fixed UMA

• PSU (tested 2) and RAM ruled out

At this point it looks like a hardware-level reset (VRM or power delivery), possibly related to running a Ryzen 5000G APU on a B450 board.

If anyone has seen similar behavior or resolved it, I’d appreciate the feedback.

Thanks.

Reboots are almost always hardware related, but make sure this has been taken care of: https://forums.unraid.net/topic/46802-faq-for-unraid-v6/page/2/#findComment-819173