giuseppe.on.usenet <> wrote:
> Thank you for your reply.
>
> > You can force Lion to run with a 32-bit kernel (by holding down the 3
> > and 2 keys at startup, or adjusting nvram settings), which would be a
> > necessary condition for running a 32-bit kernel extension.
>
> Does this page apply to Lion too? http://support.apple.com/kb/ht3773
The technical details of how to force 32-bit or 64-bit mode also apply
to Lion, including these commands for persistent settings:
sudo systemsetup -setkernelbootarchitecture i386
sudo systemsetup -setkernelbootarchitecture x86_64
The linked page referring to which models support or default to 64-bit
kernel are only applicable to Snow Leopard. Lion supports 64-bit kernel
on more models than Snow Leopard, and it defaults to 64-bit kernel on
all models which support it.
I'm not aware of an Apple article which documents this specifically for
Lion.
I tested Lion on my mid 2007 Mac Mini (before I sold the computer), and
it was limited to running 32-bit kernel. I expect the same would apply
to late 2006 and mid 2007 MacBook (which are the same architecture), and
probably the late 2006 MacBook Pro and iMac, which have the same CPU and
chipset generation (includig a memory controller with hard limit of of 3
GB RAM) but different graphics controllers.
Not sure about the 2006/2007 Mac Pro or the 2007 generations of the iMac
and MacBook Pro, but 2008 and later models of these all support 64-bit
kernel on Snow Leopard, so will default to 64-bit on Lion.
Also not sure about 2009 Mac Mini models, late 2007 or newer MacBook
models, or any MacBook Airs.
--
David Empson