Having a very odd problem. I recently updated to the newest bios (v3004) and upgraded my CPU from a 2700x to a 3950x. I have a samsung NVME SSD and an MSI 1080ti graphics card.
No matter what I do, with things exactly as they were before the upgrade, I get a hung boot. White VGA led is on, and some code like 94 or A2 (it varies) on the on-board LED.
After a lot of troubleshooting, including cleaning the PCIE contacts, blowing out the PCIE slots with compressed air, moving the graphics card from slot to slot, etc... I finally did get it to boot, but only if I manually force the slot to PCIE Gen 2. If I leave the slot in Auto or set it to PCIE 3.0, it simply refuses to boot.
My best guess is that it has to do with the 3004 bios update, as I never had any problem with anything prior to updating it to 3004 (for Ryzen 3000 series support)
Unfortunately, I don't have the 2700x anymore to swap it back in / test that. I mean, x16 at PCIE 2.0 is good enough for the card I have, but I don't like not knowing why I have to do that.
Has anyone seen anything like this before or have any suggestions?