grub + gpt (and arch, oh my)

[Michael Butash]

So taking to heart that perhaps I have simply outgrown ubuntu and its 
ilk, I decide to explore arch again.  So far, it's been painful.

In "the good old days" of everything being 512byte sectors, circular 
geometry, and new-fangled ssd with this ^2 thing, I adapted my installs 
to align things with fdisk, but most things indicated to "just use gpt" 
that "does it automagically".  Ok, except I can't seem to make it work, 
years ago last time I tried, or apparently now.

Using gdisk, I adhered to arch docs to create a small 1mb partition 
first that grub can install itself into after mbr and before the actual 
grub disk.  I thus ended up with 3 partitions, sdx1 for the bios slice, 
sdx2 for a 1g /boot slice with ext3, and the rest into sdx3 I make for 
luks+lvm pv for root and everything else.  I build this using gpt, build 
all partitions, mount them in /mnt, and pacstrap everything 
successfully.  I make the initrd, install grub to the disk, all goes 
flawlessly showing no errors.

Except my system refuses to boot off it.

Bios boot order specified that disk as first, and with my neon install, 
it did.  I ssd secure-erased with hdparm, and rebuilt with the prior 
layout, and this just refuses to work with grub, and what I presume is 
gpt complication.

Info on using gpt and NOT EFI for bios-based legacy boot systems seems 
really scarce... am I just doing something wrong here? Really just 
following these guides for arch here, the install seems ok itself, 
mostly just can't figure out why grub is being odd.  This was step one 
with an old disk and using to experiment some before I have my actual 
usage drives, ideally a mdraid set of two of these that is waiting on 
shipping atm.

https://wiki.archlinux.org/index.php/installation_guide

https://wiki.archlinux.org/index.php/GRUB#BIOS_systems

I did find some ambiguity about *which* grub to use, trying both "pacman 
-S grub" or using grub-bios packages, neither made the mobo even think 
about booting off it.

I did find some other notes in using fdisk still after gdisk makes them 
to set them bootable, which I did as well - still nada.

I'm open to some suggestions here wtf I'm doing wrong from arch, and 
general power users that have attempted using gpt.

-mb