I recently tried to install MEPIS 6.0 on a new motherboard Intel D945GCCR with a single SATA drive (Western Digital 250GB) also new.

Live CD came up fine (recognized drive as sda) and I installed with a 80GB /(root) partition, a 150 GB (/home) partition and a swap partition.

Install went as okas expected, but afterwards system wouldn't boot from harddrive. Message "no bootable media".
Saw nothing worth changing in BIOS.
Tried changing SATA cable from SATA1 to SATA0 (no affect).

Answer was:
Booted from Live CD again, Started QTParted (without sda mounted) and after selecting the sda drive, set the /root partition as "active" [QTParted reported no partition "active" prior to my action]. Committed changes , removed CD, rebooted and VOILA!!

Hopes this helps others.
Ken

Good you solved it (and helped the others by posting the solution here). Interesting, that "active" option I mean; I wonder what it does? If it's the same as "bootable" flag, then it shouldn't affect Linux (as Linux doesn't care about it as far as I know), so I guess it means something else then..

I hope somebody explained this in further detail if possible -- I'm interested, if nobody else is.