[X-post]: [OT] HDD size errors (BIOS?) (longer than usual email)

List,

I have a very odd hardware problem, and I cannot
guess, which hardware is at fault. 
(It might turn up to be a BIOS problem too, but read
on to help me out, if you can)

I have a SAMSUNG HDD, 80 GB, and everytime I power my
system up, the BIOS shows up the disk space as 33280MB
(32/33 GB approx) of HDD space, leading to GRUB also
failing to recognize the partition to boot from (or
at-least display the GRUB menu).

To actually determine what the problem is, I pop in a
LIVE CD, which should automatically mount FAT32
partitions but doesn't. So, I start a terminal and
mount them manually. I restart the machine, and voila!
the BIOS now detects the HDD as a 80 GB HDD, and the
grub menu is seen. 
If I later, shutdown the computer (with AC supply
still in) this configuration of 80 GB is lost. It
again shows up 332xx MB (32/33 GB approx) in the BIOS
and I have to reboot it through the LIVE CD and do
everything all again. Though I don't mind doing this,
I guess, it is simply a (machine) killer for the
DVD+-RW drive that I have recently purchased. 

I initially assumed it to be a problem with the Data
Cable, but it isn't so. 
Next, I assumed it to be a problem with the HDD