Z790-i PCIeX16 slot not visible - GPU not recognised

[Vee3]

Having infuriating issues with the PC I bought. Initially when booting, the GPU (4070Ti) worked fine and now it doesn't recognise/see it. I thought I might have done something with the GPU when taking the PC apart (general maintenance, paste etc) but GPU works fine in my previous setup. I've also tried putting in my old GPU (1660Ti), but no luck. GPU itself is powered on, fans spinning.

CMOS cleared, BIOS up to date, tried resitting CPU etc but again no luck. PCIEX16 in BIOS shows as not present. Tried different settings in BIOS but again it fails to recognise it. Not present in Device manager either.

It feels it can be something very simple but for the life of me I cannot figure it out. Any help would be massively appreciated!

[Jiaszzz_ROG]

Hello @Vee3 

Thank you for reaching out to us.
Could you please confirm if, in the case where the 4070Ti or 1660Ti is not recognized, the GPU fan runs during startup but the screen remains black? 
Are you using any extension cable or adapter to connect the GPUs? If so, please try installing the GPU directly into the PCIe slot and ensure that the CPU socket has no bent pins.
If the issue persists, kindly provide the following information to help us better understand your situation:
- The BIOS versions and manual settings you have tried
- The PSU, RAM model and part number, and two .txt files generated in your Windows system via the steps below:
1) Press WIN + R on your keyboard to open the Run dialog, and type dxdiag → click OK.
2) Click Save All Information and select a save location → click Save.
3) Repeat the same steps with msinfo32 to generate the second file.
- A full video recording of the issue, including the following steps:
Start recording and confirm the connections between the motherboard, GPU, monitor, and related hardware> Clear the CMOS and attempt to power on> Show the BIOS screen with PCIe x16 showing as unavailable and the Device Manager in the system not recognizing the GPU

Additionally, considering that you have recently purchased the motherboard and have already cross-tested with GPUs and have the same results, we recommend considering whether it would be appropriate to promptly contact your place of purchase for further after-sales assistance.

Thank you.