From: Andi Kleen <ak@suse.de>
To: Robert Hancock <hancockr@shaw.ca>
Cc: iforone <floydstestemail@yahoo.com>, linux-kernel@vger.kernel.org
Subject: Re: BIOS detects 4 GB RAM, but kernel does not
Date: 30 Jul 2006 00:21:59 +0200 [thread overview]
Message-ID: <p73bqr83vco.fsf@verdi.suse.de> (raw)
In-Reply-To: <44CAC249.1010605@shaw.ca>
Robert Hancock <hancockr@shaw.ca> writes:
> Athlon 64/Opteron CPUs have support for moving this part of the RAM
> above 4GB to allow it to be used. This is part of the CPU's on-die
> memory controller so no special chipset support is needed.
In cheap boards >3.5GB RAM configurations are usually not officially
supported by the vendor (= not tested) and there are systems where it
doesn't work when enabled in the BIOS (doesn't work = kernel crashes
randomly when accessing bad memory ranges)
I guess it's a subtle hint that above 3GB of RAM you should be using
ECC DIMMs anyways, which need a more expensive workstation class
board.
-Andi
next prev parent reply other threads:[~2006-07-29 22:22 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1153931278.034068.54630@h48g2000cwc.googlegroups.com>
2006-07-26 16:54 ` BIOS detects 4 GB RAM, but kernel does not Robert Hancock
2006-07-28 17:03 ` Jan Engelhardt
2006-07-28 17:06 ` Robert Hancock
[not found] ` <1153933737.200164.160870@m73g2000cwd.googlegroups.com>
[not found] ` <1154007393.940693.259680@i42g2000cwa.googlegroups.com>
[not found] ` <mH3yg.16777$2u4.7977@trnddc06>
2006-07-27 19:41 ` Robert Hancock
[not found] ` <1154112339.037481.119210@p79g2000cwp.googlegroups.com>
2006-07-29 2:04 ` Robert Hancock
2006-07-29 22:21 ` Andi Kleen [this message]
[not found] ` <fa.6TLi9h8OI9J6KX0+lv+D4/CEU0U@ifi.uio.no>
[not found] ` <fa.adpnQx0XAWgd4+g2tR5HDa2qHDw@ifi.uio.no>
[not found] ` <1154145714.279248.233230@m73g2000cwd.googlegroups.com>
2006-07-29 18:12 ` Robert Hancock
[not found] ` <1154143992.635239.225440@p79g2000cwp.googlegroups.com>
2006-07-29 18:25 ` Robert Hancock
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