Question Display cuts off after few minutes of use

[0case]

Spec:

ryzen 5 3600
gigabyte b550 gaming x
gigabyte rtx 2070 super
gigabyte 256gb nvme ssd
gigabyte 650w psu
kingston hyperx 2x16gb 3200mhz
coolermaster ML240
wd 1tb 7200

Issue:
After few minutes after switching on, the display is cut off.
GPU, Cooler, Case fans are spinning fine, power btn led is on, all led's are on, no parts heating, no beeping.
After display goes dark, OS is not running, checked by trying to ssh & telnet after display goes off and it does not works.
Tried re-assembly, jumped reset cmos, re-isntalled OS, removed ssd and only used hdd.
Happening across any os - windows/ubuntu.


No overclocks. Bios settings set to stock, also tried setting pcie x16 to gen3, gen4 & auto, it does not solves.
ssh ofcourse works when monitor is on 😅. Tried another monitor and it's the same.

Btw i've tested with 2 different LG 27uk650 monitors.


What could be the issue - faulty mobo/gpu/psu?

 

[Ninjak]

After the hang, check /var/log/syslog on the next boot for anything logged around hang time. Also check temps (CPU and GPU). I know you checked fans, but that doesn't necessarily mean temps are fine (e.g., cooler could be mis-mounted, or no thermal paste). Are temps increasing up until the hang or roughly constant?

 

[0case]

Temps are not rising. Display cut-off sometimes happen at the bios screen during boot up and sometimes during watching netflix or doing regular work like excel or games.

 

[0case]

I think I've found the root cause. It was faulty PSU. Arranged a corsair 750w 80 gold psu and machine ran perfectly fine, temps were great. Gave the gigabyte p650b for rma. I think I'll sell my PSU and get a better one. Should not have cheaped out on PSU.