Question Gigabyte B760M C POST failure with dGPU

[Patatoe]

Hello,

I wanted to ask for suggestions to further troubleshoot problems I have with a new build.

New Parts
Intel Core i5-12600K
GIGABYTE B760M C LGA 1700 Intel B760
MSI MAG A650GL Fully-Modular, 80 Plus Gold, 650W
G.SKILL Flare X5 Series AMD EXPO 32GB (2 x 16GB)
Team Group MP44L M.2 2280 1TB PCIe 4.0 x4
be quiet! Pure Rock 2 CPU Air Cooler | 150W TDP | LGA 1700

Reused parts
MSI GeForce GTX1060 Gaming 6G
Reused from the system being updated, no problems booting the older system and getting graphic outputs

The system had no graphical output when initially assembled, so I hooked up a case speaker and heard 5 beeps. The beep code pointed to CPU, RAM, or GPU failure. I started troubleshooting and removed the GPU, and the system POSTs and boots a USB installation drive no problems, the integrated graphics output from the motherboard.

I found many posts online about problems with motherboards in this scenario, specifically gigabyte, ao I started following advice I found.

I updated the BIOS firmware to f11d from gigabyte's support page, with no improvements.

I have tried enabling CSM in BIOS, I have tried disabling integrated graphics, verified the PCI slot is set as the primary display output, and never will the board pass POST with the GPU installed. The BIOS settings have been reset between trials since I obviously lose the ability to update the BIOS settings with the integrated GPU disabled.

I reinstalled the GPU to the older system to make sure I didn't break it and it POSTs, and plays games fine.

I was wondering if since the GPU is a bit on the older side if there may be some BIOS settings I need to consider that aren't stand-outs? I'm tempted to just RMA the board but don't want to do so if its a simple fix.

I have also gone through the POST sticky thread and verified whats listed there,

 

[Ralston18]

Two questions:

1) Did you use only the cables that came with the PSU?

2) Do I understand correctly that "Team Group MP44L M.2 2280 1TB PCIe 4.0 x4" means that there are 4 M.2's installed?

If there are 4 M.2's installed then check the motherboard's User Guide./Manual for supported configurations.

 

[Patatoe]

Two questions:

1) Did you use only the cables that came with the PSU?

2) Do I understand correctly that "Team Group MP44L M.2 2280 1TB PCIe 4.0 x4" means that there are 4 M.2's installed?

If there are 4 M.2's installed then check the motherboard's User Guide./Manual for supported configurations.

1, yes I only used new cables supplied with the modular supply.
2, thats a bad copy/paste job from newegg. There is 1 M.2 drive installed, the board has 2 slots total.

Regarding the M.2, its blank at this point, I have a USB drive with Win11 instalation media, and a few Linux live ISOs. If I remove the dGPU I can POST (single beep) and boot to any of those OS launchers.

 

[Ralston18]

Go to Gigabyte's website and find the applicable motherboard User Guide/Manual.

Do verify that you are on Gigabyte's website. (Just because "Gigabyte" appears in the pathname does not necessarily mean that the website is Gigabyte.)

Refer to the User Guide/Manual to doublecheck everything. Especially M.2 related installation and configuration instructions.

Hopefully just an error of omission or commission.

 

[geofelt]

Your motherboard has an 8 pin EPS port.
Is it plugged in?
The port gives extra power for graphics cards.
Is the 8 pin pcie connector plugged in to the graphics card?
Is each connector plugged into the proper outlet on the psu?

Try using different psu cables of the required type, possibly one is defective

 

[Patatoe]

Go to Gigabyte's website and find the applicable motherboard User Guide/Manual.

Do verify that you are on Gigabyte's website. (Just because "Gigabyte" appears in the pathname does not necessarily mean that the website is Gigabyte.)

Refer to the User Guide/Manual to doublecheck everything. Especially M.2 related installation and configuration instructions.

Hopefully just an error of omission or commission.

Hello, good point on the source of the manual. GBs looked to have some updates compared to the one I used online, however nothing functional seems different. I confirmed the M.2 installation, I even removed it from the board. The manual doesn't speak of any configuration settings or jumpers related to the M.2 in any case.

Without the M.2, I can only pass POST and boot the USB installation disk if I also remove the dGPU.

 

[Patatoe]

Your motherboard has an 8 pin EPS port.
Is it plugged in?
The port gives extra power for graphics cards.
Is the 8 pin pcie connector plugged in to the graphics card?
Is each connector plugged into the proper outlet on the psu?

Try using different psu cables of the required type, possibly one is defective

Thanks, this is my first use of a modular supply so I've been a bit paranoid about its installation. I confirmed the "CPU" specific 8 pin cable is plugged into the motherboard, and also a PCIe specific cable (6+2) is plugged into the GPU.

I have spares of both cables and have swapped them out, I have also moved the connections on the PSU to different sockets on the PSU in the CPU/PCIe bank of 8-pin receptacles.

With the modular PCIe cable, I have 2 separate ones which both have 2 connectors for running multiple GPUs, I have no single connector 6+2 PCIe cable. I doubt that there is a difference on the connectors for single vs multiple inteconnected GPU configurations but I guess I don't know that for sure. Is there single vs multiple GPU PSU cable configurations?

 

[geofelt]

No, the 6+2 configuration is to give flexibility to those needing only 6 pin connections.

 

[Patatoe]

I have used spare modular PSU cables for both the mother board 8-pin and PCIe 6+2 connections as well as swapping the PSU slots they plug into as well.

I have also verified the M.2 installation against the manual.

Wondering if there are other suggestions for dealing with POST failure only with a video card installed.