Question Boot/Crash Issues on build in use for several years

[survivalCat]

I have a few different issues that have showed up weeks ago on a build I put together in 2019, and am looking to gain some insight for troubleshooting. The build worked very well without issues from the time it was first put together until these issues appeared.

The first problem to appear was no power to the monitors (2) upon booting. CPU fan/LEDs, mobo LEDs, case LEDs ran as normal but there was no signal on either monitor. I would have to force shut down, turn off the PSU switch and wait a minute, turn it back on and reboot (sometimes several times) before the monitors got a signal upon booting. I replaced the power strip/surge protector and ignored this issue for a week or so by performing multiple boots until the monitors worked. The monitors are currently in use with a different system and work fine.

About a week later, the PC began to shut down unexpectedly. I would give it a few minutes, and then go through the ordeal of multiple boots, disabling then re-enabling PSU power switch, until it started up with power to the monitors. I ordered a new PSU at this time. After a day or two of this problem happening every couple hours of use, I took the old PSU out.

I then installed the new PSU and removed 3/4 RAM sticks in an attempt to isolate the issue. Since then, I have had the computer partially disassembled on a benchtop and have not been able to get any successful boot. When I turn on the PSU, the mobo background LEDS turn on. When I attempt to boot, the CPU fan LEDs briefly flash on, the fan spins for a split second, and then both CPU fan and CPU fan LEDs turn off. Mobo LEDs remain on. I have run into this same problem with both the old and new PSU, I have swapped out the single RAM stick I am using, ensured it is in the correct socket for 1 stick, and checked all the mobo power connections.

Components:

Ryzen 7 1700

ASUS ROG STRIX B350-F

Corsair Vengeance LPX DDR4 (4 sticks 8GB each)

MSI GTX 1080

SeaSonic 650W PSU (old)

Corsair RM 650x PSU (new)

It's my understanding that this mobo does not have onboard graphics so I will need a GPU connected to get a successful boot. I also suspect that there are multiple issues at play here (I have potentially caused the latest boot issue by messing something up after rebuilding with new PSU connectors) but it is hard to troubleshoot with little information in terms of isolating the issue.

Any insight is appreciated.

 

[Ralston18]

Were any connectors/cables from the old PSU or other sources used for the new PSU?

 

[survivalCat]

Were any connectors/cables from the old PSU or other sources used for the new PSU?

The old PSU was not fully modular and the new one is, so I have swapped out old>new>and now back to old connectors.

 

[Ralston18]

This motherboard?

https://dlcdnets.asus.com/pub/ASUS/...OG_STRIX_B350-F_GAMING_UM_V2_web_20170606.pdf

Any beeps (beep patterns) when computer is first started?

Is BIOS accessible? Can POST be configured to be as verbose as possible: i.e., display what is happening during boot up.....

Will the system boot into safe mode?

 

[survivalCat]

That is the correct motherboard. I found a 4 pin speaker and just tried booting again with it attached, there are no beeps whatsoever. Also noticed that the rear case fan starts to spin for a brief second before stopping just like CPU cooler fan and the CPU cooler LEDs (its the stock ryzen 7 cooler if I failed to mention that earlier). The whole process of fans spinning/lights coming on when I try to boot it lasts less than a second, no signal to any monitor connected. It then reverts back to the state of mobo lights on, mobo power LED on, but no fan activity and the CPU cooler LEDs back off.