HOWTO: ATI fglrx MTRR error fix

[sha_man]

hmm I think since my card is a Radeon 9800 XT, it should be 256MB, at least that's what it says in property dialog in Windows.

[flight_master]

Hi,

First off, to remove the bootscript:

sudo rm /etc/rcS.d/S03fix_mtrr
sudo rm /etc/init.d/fix_mtrr

The values you specify in that file are for main memory, not motherboard memory.

-Christian

[sha_man]

here the output of "cat proc/mtrr" with nothing running:

reg00: base=0x00000000 (   0MB), size=983552MB: write-back, count=1
reg01: base=0x20000000 ( 512MB), size=983296MB: write-back, count=1

[sha_man]

so?

[flight_master]

Hi,


What happens when you try:

(boot into text mode, that would mean the failsafe boot option)

echo "disable=0" >| /proc/mtrr &&
echo "disable=1" >| /proc/mtrr &&
echo "base=0x0 size=0x30000000 type=write-back" >| /proc/mtrr &&
gdm

Type the whole thing in, not line by line

-Christian

[sha_man]

ok, i did, and i got this:

[4294951.223000]mtrr: base (0x0000) is not aligned on a size(0x30000000) boundary

and entering it again, this:

4294800.712000]mtrr: MTRR 0 not used

[sha_man]

Found this on Gentoo forums:

Seems this was a bug in linux kernels >2.6.12. The bug causes MTRR's not to be set correctly on certain steppings of Intel Pentium 4's and Xeon's. Found a patch on the kernel mailing list. Here's a link in case anyone else has this problem.

http://lkml.org/lkml/diff/2005/9/28/323/1

Well i have a Pentium 4 and the 2.6.12-10-686 Kernel, but i don't know how to apply this patch

Also found a howto to fix this error, but didn't work for me, maybe for others?
http://www.rage3d.com/board/showthre...eadid=33736241

[flapane]

hi
i have the same mtrr problems, and i set up this script:
#!/bin/sh
# Fix wrong MTRR setting
echo "disable=0" >| /proc/mtrr
echo "disable=1" >| /proc/mtrr
echo "disable=2" >| /proc/mtrr
echo "disable=3" >| /proc/mtrr
echo "disable=4" >| /proc/mtrr
echo "disable=5" >| /proc/mtrr
echo "disable=6" >| /proc/mtrr
echo "disable=7" >| /proc/mtrr
echo "base=0x0 size=0x40000000 type=write-back" >| /proc/mtrr
echo 'base=0xd0000000 size=0x10000000 type=write-combining' >| /proc/mtrr

I linked it correctly in rcS and did all the things, but if I try to reboot, it seems the script doesn't have any effect at all! The mtrr is still messed with 8entries as nothing have been done. If I manually launch the script, I get
reg00: base=0x00000000 ( 0MB), size=1024MB: write-back, count=1
reg01: base=0xd0000000 (3328MB), size= 256MB: write-combining, count=1

where 1024mb is my ram and 256mb on d0000000 is my x800gt, but obviously, it's useless to change the mtrr in graphic mode...
If I boot in text mode, launch manually the script and then boot in kdm, the mtrr is still messed, as the mtrr wouldn't care about my just-launched script

[flight_master]

Hi,


Can you post the output of

 cat /proc/mtrr

, when normally booting your computer?

Regards,
Christian

[flapane]

hi
the output is

reg00: base=0x00000000 ( 0MB), size=1024MB: write-back, count=1
reg01: base=0xd7fc0000 (3455MB), size= 128KB: write-combining, count=1
reg02: base=0xd7f80000 (3455MB), size= 256KB: write-combining, count=1
reg03: base=0xd7f00000 (3455MB), size= 512KB: write-combining, count=1
reg04: base=0xd7e00000 (3454MB), size= 1MB: write-combining, count=1
reg05: base=0xd7c00000 (3452MB), size= 2MB: write-combining, count=1
reg06: base=0xd7800000 (3448MB), size= 4MB: write-combining, count=1
reg07: base=0xd7000000 (3440MB), size= 8MB: write-combining, count=1