Re: [gentoo-user] New AMD hardware. Can't boot.

[Alan Mackenzie]

Hello, Gentoo.

The saga of my new AMD Ryzen machine: I've installed Gentoo onto
(mdadam) RAID-1 on two MVMe Samsung 960 EVO M.2 SSDs, one of them being
plugged into the motherboard, the other in a carrier card plugged into
the second PCIe x16 slot.

At least, I've got as far as the point where I need to boot into the
newly installed system.  The machine doesn't boot.  In its attempts, it
displays an underline cursor on a blank 80 x 25 screen, flips this
cursor nearer the middle of the screen once or twice, then hangs.

The SSDs are partitioned with GPT.  The boot loader is grub2.  I've
taken care to follow the instructions in the Gentoo handbook to try to
avoid missing out some little detail.  However, I've never used grub2
before, so quite possibly I have missed something out.

It's also possible that the motherboard's BIOS is still too buggy to
support booting from an NVMe drive.  (It's an Asus Prime X370-Pro: I've
already had to upgrade the BIOS once (to version 0604) to get the
installation CD to be recognised at all.)

Asus doesn't have email support, they merely have an http site where one
can register and ask for help, if one doesn't mind their obnoxious
ambiguous "privacy" policy.  I do mind, particularly after having paid
good money for a product which is only partially working.

The BIOS boot sections are puzzling.  If I disable what they call
"OPROM" booting (i.e. MBR), the BIOS no longer displays the three drives
(two SSDs + DVD) as booting options.  There is an ostensible setting
called "secure boot" which is enabled, and I haven't found any way of
disabling it.

When I booted from the minimal CD, did it boot in MBR or GPT mode?  How
do I tell?

Can anybody suggest ideas to get this machine booting?  Would
partitioning the drives with MBR, and trying to boot that way help, for
example?  I really don't want to do that, though, though if it's the
only way to get my machine booting, I'd do it.

-- 
Alan Mackenzie (Nuremberg, Germany).