Question Good Signal (PG) in PSU - Problem?

[Lanzoone30]

Good Signal (PG) problem in PSU Hello everyone, a few days ago I started with the assembly of my new PC, everything was fine, until the first power-up did not give any type of image, at first I thought it was a problem with outdated BIOS, but it turns out that through Q -Flash Gigabyte managed to flash to the latest version and access the bios momentarily, since it was working with an open chassis, the problem arises that when I lift the chassis and stand it up, the equipment turns on, but it does not show any image , and if I lay down the chassis again, it turns on without problems! The first thing I pointed to was the source, so I proceeded to measure it with a tester that I have here in my toolbox, all the rails gave the normal value, but the PG signal gave 90ms and the tester produced a beeping sound . Doing some research on the internet, I found that normal is between 100-500ms. Is this the cause of the PC not turning on?

I'll leave you the components that were used and give me a hand with this, because I really have no idea what's going on...

-Processor: Intel® Core™ I7 12700K 5.0Ghz
-Motherboard: GIGABYTE Z690 UD AX DDR5
-Memory RAM: Kingston Fury 16Gb - 2x8Gb DDR5 4800mhz
-Graphics Card: GIGABYTE GTX 1660 OC-3 Fans
-SSD: 500Gb M.2 Aorus Gen 4.0 x4
-Case: Corsair MID-TOWER 4000D
-PSU: XPG Core Reactor 850W - 80 Plus GOLD

 

[DRagor]

This sounds rather like problem with GPU mounting. Since your CPU has integrated graphics start by removing GPU, connect monitor to motherboard and see if it works with chassis up.

 

[Lanzoone30]

This sounds rather like problem with GPU mounting. Since your CPU has integrated graphics start by removing GPU, connect monitor to motherboard and see if it works with chassis up.

Yes, I also tried it without GPU, and exactly the same thing happens, it turns on only with the chassis down, but if I lift the chassis it doesn't want to turn on, I also checked the connections many times and everything is in order. This is all blowing my mind...

 

[DRagor]

Yes, I also tried it without GPU, and exactly the same thing happens, it turns on only with the chassis down, but if I lift the chassis it doesn't want to turn on, I also checked the connections many times and everything is in order. This is all blowing my mind...

Hmm, chassis having a grounding problem perhaps? Or PSU not liking vertical position? Or, actually, what cooler you have on that 12700?

 

[Lanzoone30]

Hmm, chassis having a grounding problem perhaps? Or PSU not liking vertical position? Or, actually, what cooler you have on that 12700?

I bought him a Deepcool AK620, when I press the power button all the fans turn on, although with the passing of minutes they suddenly drop and increase their speed, all this with the chassis up, with the chassis down everything is normal. Could it really be a chassis problem?

 

[DRagor]

Ok, so the cooler is one of those heavy air models. If mounted incorrectly it could cause motherboard warp and hence no boot - obviously when chassis is lying on the side heatsink weight is distributed evenly even if it is installed wrong so that problem would not happen. You can remove the cooler and try without it to see if that's the problem - just make sure to shut down the system quickly whenever it boots or not to not overheat CPU (no more then 30-40 seconds running, if you need to repeat the test wait till CPU is absolutely cool again).
Next, the PSU. You can remove it from chassis so you can have it lying on its side even when chassis is up. This way you will know if it's position is affecting the boot in any way.
And finally chassis. When it is lying on side it touches ground with its metal side, thus giving it extra grounding (sort of, it's not true grounding of course). When you put it standing that grounding is gone. This can make a difference if chassis was not built properly.

although with the passing of minutes they suddenly drop and increase their speed,

This could suggest the system is trying to boot but has a problem communicating with one of the parts. The only part (aside from GPU) that could be affected by chassis position is M.2 drive so make sure it is installed securely and does not move.