FreeBSD 6.0, amd64, A8N-SLI and 4gb ram

[Joseph Kerian]

On 2/11/06, Robert Leftwich <freebsd at rtl.fmailbox.com> wrote:
>
>
> On Sat, 11 Feb 2006 23:19:07 +1100, "Robert Leftwich"
> <freebsd at rtl.fmailbox.com> said:
> > I've been running FreeBSD 6.0 stable on an A8N-SLI Premium amd64 box
> > with 2gb of ram for a few weeks now and it has been running well,
> ...[snip]
>
> Forgot to mention, I'm running a kernel with 'options SMP' + GENERIC
> minus one or two of the non-applicable options.
>
> Robert


I was planning on purchasing one of these boards in the near future, so I'm
rather interested if you have solved this particular problem. In no
particular order, my suggestions are:
-The A8N-SLI's are extremely picky about the RAM you give them; have you
double checked with a memtest run to verify that it's not the problem? Also,
what happens if the new RAM is the only RAM in the system?
-Does anything change if you compile for a single processor? FreeBSD should
run fine even if it's not taking advantage of the dual cored nature of the
processor.
-There appears to have been a bios problem with using exactly 4 gigs of ram
in the A8N Deluxe boards at one point, not sure if this also showed up on
the Premiums or not. You may want to verify that you are running the most
recent bios.

I found the cause of the invalid option error.  From the handbook section on
the PAE option:
"*Note:* The PAE support in FreeBSD is only available for Intel IA-32
processors." Note that it appears that PAE is a system for addressing _more_
than 4 gigs of RAM (handbook section 8). Since your board only supports up
to 4 gigs (
http://www.asus.com/products4.aspx?modelmenu=2&model=539&l1=3&l2=15&l3=148),
I guess I'm curious why the PAE options exist in the bios.

Regards,
Joe