GEN-Z.2 reduces PCIEX16_1 lane width?

[dblouis]

I have a Crosshair X670E Extreme motherboard. I wanted to add additional m.2 ssd and noticed on the user manual that PCIEX16_1 would run X8 when M.2_2 enabled while there was no reference to GEN-Z.2. So I installed 2 SN850X 4T on the GEN-Z.2, only to find my graphic card running at PCIe  ×8. Did I configure something wrong or every m.2 ssd installed after the first one reduces PCIEX16_1 lane width?

[dblouis]

I unplugged GEN-Z.2 and found my GPU still running at 4.0 ×8, guess I had been running at ×8 all the time. I had been using M.2_1 for my only ssd and PCIE×16_1 for my GPU with a PCIe 4.0 ×16 riser cable, which should not have reduced the bandwith.

[Silent_Scone]

Hello,

does the GPU operate at 16x when plugged in directly? Riser cables can sometimes be temperamental, always best to remove them from the system entirely if troubleshooting.

[dblouis]

Yes it does. In fact, I reinstalled the GPU vertical holder and it is running properly at ×16 now.

[Silent_Scone]

Awesome. The ribbon cables can be cantankerous at times. Glad it's resolved 🙂