I had to pull the GB TR AIC from my TRX40 build in the latest Big Sur 11.3+ due to freezes. This card is one I've used in previous Z390 and X570 builds. I re-flashed tonight using the recommended firmware from the repository and Big Sur now seems stable with the TR AIC. Thanks!
I know this is another mobo and I'm not asking for help, but I saw one interesting change with this firmware update: DSB2 no longer contains a USB port (shown in Spoiler). This port only appeared after changing the SMBIOS from iMacPro1,1 to MacPro7,1 when using the previous firmware.
In testing checksums, I'm now not certain what firmware I'd flashed onto the chip. Using Hex Fiend, it says in the DROM section, "GIGABYTEZ390 DESIGNARE", so maybe a version intended for the Z390 mobo. There are no matches with NVM 20,21,23,33,43,50,71.
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