tonyqiu1019

Somnambulator
I get the same thing with my 3080 FTW3 hybrid. I installed PX1 (probably for the first time, it was not already installed) and it immediately popped up a messaged to perform a vbios update (before even loading into the app). the progress bar filled, the screen flashed briefly, and I think it said the update was complete.
 
however once i was inside the app I clicked on the Rebar page and have the same experience as the OP. I click to install the vbios update and it immediately crashes and I have to relaunch PX1. Maybe it's not detecting my card was updated.
 
Also, Rebar is enabled in my UEFI but PX1's Rebar page says to check with my mobo MFG- i assume the app can't detect it, but this means it may actually be enabled. If not, then this is broken to, as Rebar is enabled in my UEFI. It was running with my previous GPU, confirmed by nvidia control panel.

That's helpful. Some of the symptoms like performing a firmware update upon installation of PX1 was exactly the same as mine, despite that I did not mention it in my initial post. Now that we could maybe conclude this is potentially a widespread issue, hopefully we could have someone look into it and find a solution.

tonyqiu1019

arestavo

tonyqiu1019

Somnambulator
I went around PX1 and am good now.
 
There was a newer vBIOS available, but PX1 was crashing during install. I found an official thread for my card with the latest vBIOSes posted (i don't have permission to post URLs yet) and manually installed the default vBIOS. after rebooting, Rebar page in PX1 shows all green checks and nvidia control panel confirms rebar is enabled.

Doesn't work for me though... every new version of BIOS I tried game me an error of "no compatible display adaptor found". Something weird is going on for sure.

The 3090s have a new revision (original is 0.1, new is 1.0) that addresses the power load balance issue. It sounds like you have the latest revision board that isn't compatible with those posted REBAR updates (Jacob says as much in his post). Contact EVGA to get the compatible executable: 

Thanks for pointing me in the right direction! I did not end up contacting support; instead searched around to find the correct BIOS for my revision 1.0 card, and ran the update executable by myself. Now ReBar shows "enabled" in NVCP and PX1, and it's all good :)
 
To anyone who's wondering, the 3090 FTW3 ULTRA cards have an original model number 3987, which is reflected in any BIOS executable file names for this card. Those were what I tried last night, and they were all incompatible. However, the revision 1.0 cards apparently have a different model number 3982. So I searched "cdn.evga.com" together with "3982" as the keywords, and I found the link quite easily. Now I downloaded the 3982 BIOS, and it worked like a charm.
 
Hopefully if you have a different card (e.g. 3080 FTW3) with revision 1.0 variations, you could try and apply a similar process: find the updated model number for your particular card, and search Google to find the BIOS file.