Z890 Hero GPU Running at X8

[mattbirk6]

Hello all, I see others have reported this issue as well.  I've read the various other postings, doesn't seem to be a conscientious as to the correct resolution.  From what I've been reading online, people are saying it's a Bios issue, and rolling it back is the only way to get it working.  I hope that is not the case?

My setup. 

Intel 265F (planning on upgrading to the 285K) , Aorus RTX 5090 Master Ice Edition, and a total of three nvme drives.  My OS drive a Samsung Gen 4 990 Pro is currently in  the M.2_2 slot (I've tried M.2_1 as well) and my two storage drives are in M.2_5 & M.2_6, controlled by the chipset.  First storage drive is a WD Black SN-850X 2TB, the second is a Crucial T710 4TB,  I know the T710 is gen 5 but I'm not concerned about it's speed, I bought it cause of it's capacity and Amazon had a sale on them at the time.

What I've tried.  Reseating both the cpu and gpu.  Verified I'm on the latest Bios currently version 3002, and the latest management engine software.  Verified while GPU was underload in Furmark that the GPU was still reporting to be in X8 mode.  I started a support ticket with an ASUS script reader.........excuse me, I mean highly skilled and trained support technician. 🙂  But I have to wait for them to call me.  I'd bet my house I'll get better insight into this problem from the community, hence my posting here.  Appreciate any insight anyone may have.  Thank you.

[cvarta01]

Z890 Hero with 285K here. Same exact 8x issue out of box with my 5070 back in April. Tried a ton of things and eventually got it to change to x16 mode. Turning off any fast boot options in the bios and clearing CMOS via the button on the board I think is what did the trick. If you A/B test with enough things in the BIOS, it will eventually change to x16. There is some timing issue with the speed being detected at boot with the BIOS. I think the settings below with hard reset of the CMOS settings beforehand is what solved it for me. I don’t think it’s a bad board, at least bast on my experience. Hope this helps.

Fast Boot [Disabled]
Boot Logo Display [Disabled]
POST Report [5 sec]

Internal Graphics [Disabled]

[mattbirk6]

Hi there and thank you for replying.  You know what, I will certainly try that, and report back.  Thanks

[mattbirk6]

Thanks very much for your input, but I've spent the better part of a day messing around with the Bios settings, no change.  Supposedly someone from ASUS will be calling me.  If they don't come up with a solution, the board is going back to Amazon.

[mattbirk6 · Accepted solution]

Update: 

Problem solved!  All it took was a new board. lol