No grub screen or boot after upgrade to jessie

[Robert S <robert.spam.me.senseless@gmail.com>]

Hi.

I have had a functioning system on wheeze using grub2.  I did an
upgrade to Jessie according to the debian docs.

Now when I boot my system I simply get a black screen after the POST
screen - there's no GRUB screen or any hint of it.

I've managed to boot my system with a live USB stick and have entered
my system in a chroot.

In the chroot I tried downgrading to grub-legacy and got the same
result.  I purged all of the config files from GRUB2 then reinstalled
GRUB2 from scratch.

I have repeatedly run update-grub/update-grub2, and grub-install /dev/sda

Here is as much info as I can give:

Hardware: Gigabyte Brix GB-BXBT-1900 with Samsung SSD 850 EVO 4G RAM.
Debian - x86

debian:~# dpkg -l |grep grub
ii  grub-common                      2.02~beta2-22
i386         GRand Unified Bootloader (common files)
rc  grub-legacy                      0.97-70
i386         GRand Unified Bootloader (Legacy version)
ii  grub-pc                          2.02~beta2-22
i386         GRand Unified Bootloader, version 2 (PC/BIOS version)
ii  grub-pc-bin                      2.02~beta2-22
i386         GRand Unified Bootloader, version 2 (PC/BIOS binaries)
ii  grub2                            2.02~beta2-22
i386         GRand Unified Bootloader, version 2 (dummy package)
ii  grub2-common                     2.02~beta2-22
i386         GRand Unified Bootloader (common files for version 2)

debian:~# update-grub2
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.16.0-4-686-pae
Found initrd image: /boot/initrd.img-3.16.0-4-686-pae
Found linux image: /boot/vmlinuz-3.2.0-4-686-pae
Found initrd image: /boot/initrd.img-3.2.0-4-686-pae
done

debian:~# grub-install /dev/sda
Installing for i386-pc platform.
Installation finished. No error reported.

My grub.cfg: https://www.dropbox.com/s/5xz5mrbagwcgpp5/grub.cfg?dl=0

debian:~# gdisk /dev/sda -l
GPT fdisk (gdisk) version 0.8.10
Partition table scan:
  MBR: protective
  BSD: not present
  APM: not present
  GPT: present
Found valid GPT with protective MBR; using GPT.
Disk /dev/sda: 234441648 sectors, 111.8 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): F387E81C-204F-43B0-ACA8-C169094F79B5
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 234441614
Partitions will be aligned on 2048-sector boundaries
Total free space is 126167917 sectors (60.2 GiB)
Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048          206847   100.0 MiB   EF02  BIOS boot partition
   2          206848        41166847   19.5 GiB    8300  root
   3        41166848        45361151   2.0 GiB     8300  Linux swap
   4        45361152        87304191   20.0 GiB    8300  var
   5        87304192       108275711   10.0 GiB    8300  home

I would be very grateful if someone could help here.