Fri Jul 11 16:45:03 EDT 2014
Managed to break booting on 2 pcs switching to systemd wheezy->jessie.
One was fixable by mounting the main sata drive using a usb cable on a different PC.
The other one got messed up.
I only ever installed grub on a different machine using the old grub.
I don't know how to do grub2 in a chroot on a different machine, so
I'm booting Debian installer as rescue.
Either use tftp or burn the netinst to a cd-r:
Start it up
mount /dev/sdx /my-root
cp -av /dev/sd* /my-root/dev/
mount -t proc proc /proc
apt-get install grub-pc
then install some kernels