What is the largest hard drive possible for a 32-bit operating system and why?

Here's a 14" platter.  That's as large as I'm aware of --
http://members.fortunecity.com/pcmuseum/hardisk14inch.jpg

I'm pretty sure he was refering to the largest number of
megabytes/gigs/terra rather then diameter :)

Hello,
         I deal a lot with computers and the biggest I have ever heard
of is 800 gigs.  Fantom Drive's external goes for about $2300 here
(http://www.pcrush.com/prodspec.asp?ln=1&itemno=75318&refid=1050).  If
that's a bit pricy, 500 gig models are more in the $350 range.
                                                    Sam

In general for any generic operating system there is no upper limit
beyond what the hardware is capable of.  A 32 bit OS will use machine
instructions with 32 bits each, which says little about the
addressable harddrive space.

1)  If you address each byte individually, and you only use 32bits
worth, you can address 2^32, or exactly four gigabytes.
2)  Similarly, if you address each byte individually and you use 64
bits worth, you can address 2^64, which is 17,179,869,184GB (yes,
that's right - roughly 17 billion gigabytes).

It is likely that any modern design that you find will have this as
it's upper limit, since most 32-bit OSes perform memory operations on
multiples of 32, and this is more than any needs right now.

It should also be noted that this is not actually a scheme that is
often used.  There are few if any modern filesystems that address
bytes;  all of them refer to units far larger than this, allowing them
to refer to much larger sections.

RAID 0, SLED's

Around a thousand bucks per Terabyte for a quality drive and you can
stripe across at least 8 drives.