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From: steve@Watt.COM (Steve Watt)
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Date: Wed, 26 Aug 2009 15:53:36 -0700
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Cc: 
Subject: Re: enable ECC in OS code?
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In <4A954A35.4030207@icyb.net.ua>, avg@icyb.net.ua wrote:
>
>Here is a question that I am afraid I know an answer for.
>I have some ECC capable hardware:
>1) Athlon II with embedded memory controller that can do ECC
>2) DRAM modules with ECC
>Assuming that ECC data lanes are connected between the two on motherboard, and
>given that BIOS doesn't perform any ECC setup (nor there is any option to control
>that) - would it be possible to turn on ECC from OS code?
>Or is it too late in the game already?

It's about 100 times easier to have the BIOS do this.  First off, it's
usually quite specific to the chip set exactly how to do it.  Next, if
ECC wasn't enabled previously, the ECC bytes will all be wrong, which
means that you'll have to rewrite all of memory after you've turned it
on.  Oh, and you have to fetch the code that rewrites the ECC from the
memory with incorrect ECC to do that.

If the BIOS is broken to the extent that it doesn't enable ECC on a
system that it should be available, whine at the vendor.

-- 
Steve Watt KD6GGD  PP-ASEL-IA          ICBM: 121W 56' 57.5" / 37N 20' 15.3"
 Internet: steve @ Watt.COM                      Whois: SW32-ARIN
   Free time?  There's no such thing.  It just comes in varying prices...