Bug#524342: Same problem here, unable to install Grub
System: Gigabyte GA-M57SLI-S4 mainboard with NVIDIA MCP55
3x Samsung EcoGreen f3 1.5 TB
Trying to install Debian Squeeze on a Raid1 ext3 of 2x 40GB partitions at the start of the Samsung EcoGreen drives with one hot spare (third drive, same partition).
Grub2 won't install on /dev/sda (first hard drive). After trying to install Grub2 I tried Grub-legacy and Lilo, but all failed. I was unable to complete installation.
I used d-i from 26th of September (20100926) and from 1st of October (20101001).