On Fri, 2005-06-24 at 01:37 -0400, Peter Arremann wrote:
> How does that work? :-)
It works on the reality that the 32-bit Athlon and 64-bit Athlon use the
_same_ 40-bit/1TiB EV6 addressing to memory (as well as tunneled over
HyperTransport to other CPUs and I/O in the case of the latter). In
reality, they are the same core designs too (the latter just being
revamped ALU with 64-bit features, more 128-bit XMM registers and the
evolution of its on-CPU AGPgart to the I/O MMU).
Normally the 32-bit Athlon is limited in its addressing to 32-bit/PAE36
(4/64GiB) for Intel GTL compatibility at the BIOS, OS, etc... If you
have a BIOS that lets the 32-bit Athlon break 32-bit/PAE36 Intel GTL
compatibility, and pair it with an OS that does the same, then you can
have the _full_ support of 32-bit Athlon's EV6 addressing architecture.
In fact, EV6 is _nothing_ like GTL, but it just emulates it. That
includes it looking like a "SMP bus" in the case of Athlon MP, when --
in fact -- it's an "MP switch."
If you want to know more about the non-PAE36 >4GB Linux hack and the few
Athlon MP mainboards with BIOSes that support it, read up on the LKML
circa February 2004.
--
Bryan J. Smith b.j.smith@xxxxxxxx
---------------------------------------------------------------------
It is mathematically impossible for someone who makes more than you
to be anything but richer than you. Any tax rate that penalizes them
will also penalize you similarly (to those below you, and then below
them). Linear algebra, let alone differential calculus or even ele-
mentary concepts of limits, is mutually exclusive with US journalism.
So forget even attempting to explain how tax cuts work. ;->
