MTRR fixup?

Rink Springer rink at
Wed Sep 3 16:17:41 UTC 2008

Hi Bernd,

On Wed, Sep 03, 2008 at 05:49:44AM +0200, Bernd Walter wrote:
> Some boards (including my Intel DG33BU) seem to have problems setting
> up the mtrr to cache all RAM.
> My system runs fast with 2G and ist about 6 times slower in buildworld
> with 6G RAM.
> I will try a BIOS update once Intels tells me why their update ISO
> just turn the system off instead of updating the BIOS - sigh.
> But it seems that Linux is doing some kind of fixup for MTRR:
> Can we do something similar?

This is interesting, my motherboard (Intel DP965LT) seems to suffer from
the same problem: putting 4GB of memory in it makes it dog slow, while
putting 2GB in it makes it lightning fast...

I've just given up trying to put 4GB of memory in this machine, but I
believe this may help...

Please, keep me posted if the BIOS update fixes it for you.


Rink P.W. Springer                                -
"Anyway boys, this is America. Just because you get more votes doesn't
 mean you win." - Fox Mulder

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