Boy, here I am an old DOS dog and I still can't find my way around these GUI thingies on our machines these days.
I just built a system not even a month ago (the one I'm using right now!) and I decided to go with only one big drive, so I got a SATA 120 Gb one. "I'm smart!", thought I, going with 120 Gb, which is just under 137 Gb, the Line of Demarcation for the newest forms of Windows, so I don't have to worry about their inability to recognize drives over 137 Gb. Well, it turns out that SATA drives are controlled via separate chips on the mobo, so it wasn't even problem! (Rats! I could have gone after a bigger HD!)
"Well," says I, "I'm still smart, for SATA is FAST!"... except bonehead here enables the OTHER SATA controller and my bootup and POST phase was always rough! I didn't figure out until THIS morning that I had to go into BIOS and disable the other SATA controllers, as the BIOS was looking for it and sometimes, this caused the system to hang either during or right after POST.
My upshot from this Shaggy's Scoopy Doo Doo story for TOCXOBearslayer? Well, Cueball has a point- plumb the BIOS menus and see if there is a quick and easy way to enable the extra Gb to be seen without spending more money. Again, also check MS's site. I could've sworn there was some d/l there that was supposed to help with this exact problem. If I can find the gumption, I'll poke in there again and see if I can stumble across it again.