[UPDATED, unsolved] No post

[john01dav]

Hello,

 

I just built a new computer (parts list, ssd is different). When I turned it on, this moment that should be glorious was instead dreadful: there was no post. More specifically, the monitor had no output, the case and CPU aio fans pulsed on and off for a few seconds, and then the computer stabilized with just the PSU fan on, everything else off, and a faint blue light between the CPU socket and IO shield.

 

Here is what I tried (#1 happened first, the rest are not ordered, as I do not remember the exact order):

1. Press all PSU connectors in, on both the PSU and not-PSU side. This made the blue light and fan pulses go away, but did not fix the issue.
2. Clear CMOS, no change
3. Remove everything but one stick of ram, CPU, PSU, Motherboard, and CPU cooler, while plugging into igpu's HDMI output. No change
4. Move the stick of ram to each slot, testing with each slot. No change
5. Repeat previous step with other stick of ram. No change
6. Move CPU power connector to the 4 pin connector while disconnecting the 8 pin connector. No change

This motherboard has a very weird power connector (see attached image). It appears to be an 8 pin CPU connector next to a 4 pin CPU connector. My PSU, however, only has a single CPU cable, despite being fully modular, so I can't plug both in. On the advice of LTT's Discord, I plugged in just the 8 pin connector, leaving the 4 pin empty. There are also no lights on the motherboard (that turn on), and plugging in an external speaker to hear beep codes results in silence.

 

At this point, I am thinking that either the motherboard, CPU, or RAM is dead, but I have no way to check which as the newest other desktop that I have is a FX-8350 with an AM3+ motherboard and ddr3 ram. I very much hope that it is some other issue, however, and that I can fix it to get this system that I have already waited too long for working. As such, I ask 1) what

else can I try to fix this and 2) if it is a dead component, how do I know which one (or more) to RMA?

 

Other notes:

• I am extremely careful with static electricity, using an anti-static wristband, anti-static bags (but not when components are running, of course), and frequently touching the case and PSU.
• The computer blew a 10A circuit breaker with AFCI (but not GFCI) once. This circuit breaker is known to be finicky (blowing with even a known working laptop that doesn't blow anything else), but not ever with the outlet that this computer was plugged into.
• The specifics of the lack of post are that there is no signal on the monitor. I tried two different known good monitors.

 

If I left anything out, plese tell me.

[Linker]

You worded it a little strangely...

Did you hear beep codes or not?

[john01dav]

1 hour ago, Linker said:

You worded it a little strangely...

Did you hear beep codes or not?

Last night, I heard no beep codes because I had no motherboard speaker. Just now, however, I found one in a different computer and plugged it in. There are still no beep codes.

[john01dav]

UPDATE

 

I just tried putting in another PSU to see if the CPU power delivery mechanism is to blame. I plugged this PSU into just the 4 pin CPU power connector and activated it by shorting the green and black pins on the 24 pin connector, using the PSU's switch to control whether or not it is on. When I start the new PSU and then immediately after start the main computer, the same issue happens (No video display, no signs of life). Then, after ~5-10 seconds, the new PSU turns off, and sometimes the main one does too. Does this mean that I have confirmed a dead motherboard?