Hi GNUser
A 32 bit kernel can manage 4 gigabytes of address space. Part of that space will be reserved for
video, audio, Ethernet, and other hardware on the motherboard. So a 64 bit motherboard with
4 gigabytes of RAM may only be able to access 2.5 or 3 gigabytes of RAM when booting a 32 bit
kernel. If you boot with Core64 (not Corepure64) you can run 32 bit apps and access all of your
RAM. More importantly, if you have more that 4 gigabytes of RAM, you will be able to utilize all
of it.
Why would you do want to do that? ...
Someone gave me a 64 bit netbook with 2 gigabytes of RAM (non expandable) that refused to
boot a 32 bit kernel. With 2 gig of RAM there is no need or reason to run 64 bit extensions.
32 bit programs tend to be smaller and have a smaller native data size.