No video output if case is not upright on new build

[wgctwa]

I just tried putting together the following build:

• EVGA FTW3 3080
• Ryzen 5600X with stock cooler
• Gigabyte Aorus Elite x570
• 4 sticks of Crucial Ballistix RGB 8 GB DDR4-3600 CL16 RAM
• Asus ROG Strix 750 W power supply
• A Samsung 500GB SSD that I got OEM from an MSI laptop (I've confirmed it works in other builds)
• Phanteks p400a case

I used QFlash to update the BIOS but I'm only getting video out half of the time. It's either booting to Windows 10 properly or there's no output at all.

I've isolated some conditions:

• No output if the case is lying on its side
• If I insert the GPU, press it in firmly and then put the case upright it will boot
• If I move the case after that it won't output again until I reseat the GPU

The GPU sags a bit but holding it up and booting doesn't solve the problem. It came with a "mounting bracket" but it's just a small piece of metal (link to picture) and I don't know where on the case I can attach it to.

Should I get the Phanteks vertical gpu bracket (link here)? I heard it can impede airflow and the power cables to the card are already touching the glass when i put it on. Also it might be a motherboard problem and there's no guarantee the bracket will solve it.

 

I'll try getting a second GPU (need it for another build anyway) today. If that doesn't work I'll assume it's the motherboard slot that's faulty, which would be the best case I think.

 

Any suggestions for what I should try or how I can improve the mounting of the GPU? Am I correct in assuming this is most likely NOT a CPU issue?

 

[cr8tor]

Have you checked the monitor cable at the monitor end?

It seems odd the way this is acting. Makes me wonder if something else is going on thats not being noticed when the PC is moved, tilted, ect.

[wgctwa]

44 minutes ago, cr8tor said:

Have you checked the monitor cable at the monitor end?

It seems odd the way this is acting. Makes me wonder if something else is going on thats not being noticed when the PC is moved, tilted, ect.

I did. I've confirmed the monitor works with that specific cable using a different computer. Also checked all connections and made sure everything is plugged in properly. Should note that the decorative LEDs on the RAM, motherboard and GPU and case fans run even when there is no output.

 

I am guessing its either a motherboard or GPU problem where the PCI connection is faulty. Should I try tilting the PC from a standing to lying position while it's running or is that a bad idea?

[cr8tor]

1 hour ago, wgctwa said:

Should I try tilting the PC from a standing to lying position while it's running or is that a bad idea?

Its a bad idea if you have a hard disk drive (HDD) with a spinning disk. Or an optical drive that's spinning.

If you only have SSD storage than you are fine to move it while its on.

And yes, it's a good step to try and see whats causing this.

[wgctwa]

On 11/27/2020 at 2:54 PM, cr8tor said:

And yes, it's a good step to try and see whats causing this.

Tried this and it doesn't seem to have an effect while the machine is running, but will cause it to not boot after it's turned off and moved. Looks like it's an issue with the chipset fan blocking the extra-large graphics card from seating correctly. Moved the GPUs around and it's just this GPU and this motherboard that have a problem.

How absolutely braindead does Gigabyte have to be for their GAMING motherboard to not fit a GAMING graphics card. If they had moved the fan down 2 cm or made it 5mm lower this wouldn't be a problem.

It's too bad I bought it from Canada Computers so it can't be returned for a model that had proper design considerations.

 

EDIT: Replaced the motherboard and things seem to work now. The 3080 still won't click into the first PCIe slot, but at least it outputs video now.