Noted at http://www.48bitlba.com/ may answer this.
Keep in mind that the OS matters too. DOS based Windows drop dead at 127GB. NT/2000/XP drop dead there until Service Packs are applied.
I have a five year old HP Pavillion 6736 with 20gigs internal and 40 external. Both are filling up fast and I'd like to get a larger external drive. I've been told in the past that my computer would only recognize up to 80gigs, however, I've also been told that I can get a 160gig and partition it. My question is, first, is it true that my machine will only recognize 80 gigs and if so, how can I partition a 160gig drive to create two 80's