I have an MSI K9A Platinum motherboard (AMD CrossFire 580X and SB600

chipset) with 4G RAM, and I'm running Fedora 9 (x86_64) with kernel

2.6.25.11-97.fc9.x86_64.  When I boot, I see the following go by:
Checking aperture...

Node 0: aperture @ 1006000000 size 32 MB

Aperture beyond 4GB. Ignoring.

No AGP bridge found

Your BIOS doesn't leave a aperture memory hole

Please enable the IOMMU option in the BIOS setup

This costs you 64 MB of RAM

Mapping aperture over 65536 KB of RAM @ c000000

PM: Registered nosave memory: 000000000c000000 - 0000000010000000
My BIOS doesn't have an IOMMU option (latest BIOS available for the

mboard).  However, it appears that an aperture is allocated but the

kernel then ignores it due to where it is placed.  Why?
Is there anything I can or should do about this (what impact does this

really have)?
--

Chris Adams <cmadams@hiwaay.net>

Systems and Network Administrator - HiWAAY Internet Services

I don't speak for anybody but myself - that's enough trouble.

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You can't use it as an IOMMU to handle 32-bit devices, since it's above

the 32-bit addressible region.  Hence the kernel doesn't use it.
	-hpa

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32MB is normally not a useful aperture. Likely it's some garbage 
It will eat your babies. No really except for some lost RAM nothing.
-Andi
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