Is my computer going crazy?

bought a new computer, picked it up yesterday, already taken it back for repairs…

but I am slightly confused about one thing.
here are the specs:

Intel Core i7 920
MSI X58 Pro
6GB RAM
1TB HDD
EliteGroup Nvidia 9800GT 1GB
Vista Ultimate 32-bit

now originally I wanted 64-bit, as I had always been taught 32-bit respond only to 3.32GB of RAM (or there about), so why does my 32-bit machine respond to 6GB of RAM?