Hi to all,

I have the following problem, maybe common to others even if I was not able to find a solution in the forum:

We had a dual dual-core opteron (opteron 275) computer with Asus K8N-DL motherboard (Phenix BIOS) and 6 Gb of RAM (6x1, bought in april 2006). It has a linux partion (suse 10.0) and a small windows partition (30Gb, mainly for "safety" reason, essentially never used).

Now memory had been upgraded to 12 Gb (6x2Gb) but it is not possible to boot linux.
Suse freezes and only gives a black screen.

I tried to upgrade to Suse 10.2 or install Fedora 6 (they had been installed without problems in similar workstations...) but Suse does not install (black screen) and FC6 gives a problem:


Checking aperture...
CPU 0: aperture @ 12000000 size 32 MB
Aperture from northbridge cpu 0 too small (32 MB)
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 12817793024 KB of RAM @ 1288490188

...but then nothing

(I hope to have copied all correctly (maybe some error in the numbers).)

I tried to boot the installed version of suse 10.0 with some options: for example

iommu_debug=y mem=4096M

gives:

CPU0: Machine check exception
TSC 2b054d55b6
kernel panic -not syncy: Machine check

I tried also

iommu=65536

or

iommu=soft swiotlb=65536

but no result (system freezes with a black screen). (in tried the same options installing FC6 but no improvement)

So, the question:

1) How can I set the memory hole? I did not found any such option in the BIOS!
2) there is a boot option to correct it?

Thanks a lot in advance for your help.

This document might help with the "memory hole" issue:
http://www.debian.org/releases/stabl...h03s06.html.en

Thanks, the problem is maybe that there is no memory hole configuration in my BIOS... so that I cannot disable it.