Question GPU don't show up in bios

[kanaron]

Hi, I just upgraded my PC and I have problem with old GPU
Spec:
CPU: Intel i5 10400 (box cooling)
mobo: Gigabyte Z490 Gaming X
RAM: 1x Kingston HyperX Fury 16GB 3200MHz
PSU: be quiet! Straight Power 11 80+ Platinium
Storage:
M.2 Samsung 970 EVO Plus 500 GB
HDD Seagate Barracuda 1 TB (old)
HDD Seagate Barracuda 512 GB (old)
GPU: Gigabyte Nvidia GF 1050 GTX (old)

At first I builded PC without old parts (both HDD and GPU). Using integrated GPU I installed Windows 10, all mobo drivers and everything works great until I installed old HDD's and GPU.
1050 is not showing up in bios. In easy mode I can see in PCI section "PCIE16 N/A". But when I start PC GPU fans starts spinning for 1 second, RGB is on all the time and backplate get wormer
When I pluged hdmi to 1050 I got 4 long beeps and VGA LED is on which indicate that there is no hdmi connected to mobo (I checked without 1050 and without hdmi to mobo, same 4 long beeps)
What should I do to solve this? I want to turn off integrated GPU in bios, but I'm not sure if I should do that. Alos I think if I should clear CMOS? Or check GPU on old PC? But yesterday GPU works great on old PC

 

[kanaron]

I just changed PCIe slot from first (PCIEx16) to second (PCIEx4) and it worked, but does it mean that slot PCIEx16 is broken? Should I return mobo to shop?