Question RX 5700 XT is stuck on PCIe 3.0 x8 ?

[Inver_ShaRingan]

I built an ITX build as below:
ASRock A520M ITX /AC (with latest BIOS 2.20)
Ryzen 5 5600X
RX 5700 XT
16Gb 3200 cl16
1Tb M.2 P3
NZXT H1 case

And after installing all, setting up fan curves, and XMP profile + enabling SAM in bios. I noticed that there is GEN 4.0 PCie able to turn on, but i guess it doesn't work with riser in NZXT H1 V1 case (new version) ?

But no matter what settings I try, the GPU is stuck on PCIe 3.0 x8 ?

Is that limitation of this mobo ? Even if website said is PCie 3.0 x16. Something with CPU ? I screw pump on CPU too much ?

 

[Fix_that_Glitch]

What is reporting it as 3.0 x8? My guess would be the riser is the problem.