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Re: Question : grub commands

Am Dienstag, 15. August 2006 15:14 schrieb Lennart Sorensen:
> On Tue, Aug 15, 2006 at 06:27:32AM +0200, Hans wrote:
> > Sorry, I maybe did not ask correctly. It is not the problem, that the
> > time is not shown correctly. The background is, that other timings are
> > running in double speed, too (i.e. keyboard clock and some other). This
> > is a known problem on AMD mobile processors and was discussed in earlier
> > days. The solution of it, was to add "disable_timer_pin_1" in the boot
> > vcommand on grub or lilo. Now I read about adding "noapictimer" should
> > solve this, too. My question aimed to an technical answer, if the
> > commands "disable_timer_pin_1" and "noapictimer" are doing the same, or
> > if they both solve the mentioned problem in different ways.
> I believe the problem occoured with ATI chipsets on laptops.  As far as
> I have understood it, the problem is that the timer interrupts occour
> both on the 8259 interrupt controller, and through the apic.  I believe
> 'disable_timer_pin_1' makes the kernel ignore the 8259 interrupt for the
> timer, and that 'noapictimer' ignores the apic interrupt for the timer.
> Since the problem seems to be getting two interrupts for every timer
> event, one for each interrupt method, it makes sense that disabling
> either one will solve the problem.  It doesn't matter which one you
> disable as long as you disable one of the two.
> It really looks like a bug in the design of the chipset, although it may
> just be that the BIOS/ACPI tables are done wrong, which is rather common
> it seems.  Too often the ACPI tables for windows work, but are
> incomplete or wrong for other operating systems.  Apparently on such
> systems, telling linux to lie to acpi and pretend to be windows xp often
> solves such strange problems.
> --
> Len Sorensen

Hi Len !

It seems, that in last kernel 2.6.17 this problem is solved. I read the 
documentation of the kernel, and (as you wrote), these timers just misbehave 
if you have a chipset of ATI. This is the case on my notebook: ATI chipset !

Well, without this kernel-command it is running fine with the newest kernel. 
So there are no problems any more. I additionally did hope, that this could 
be the reason, why my 3D-accelertion with the "fglrx"-river is still slow. 
All 3D-functions are o.k., I get the box with the rotating wheels when 
starting "fgl_glxgears", but they are rather slow. About 50 FPS, that is 
speed as mesa-glx shows ! Should be 600 FPS, that would be o.k. "fglrxinfo" 
shows the correct driver-version, and "glxinfo |grep direct" shows  "direct 
rendering: Yes"

So verything seems t be o.k. with the software, and my idea was, something 
else, but not the driver is braking my system.

You can believe me: I checked really everything, and do not know, where to 
look now. 

Additonally I tested every xorg.conf I found in the web and checked a whole 
bunch of settings. Sadly no success ! ATI really sux ! (This notebook I got 
as new of a guarantee as exchanged, I had Nvidia-card on the other noteook).

And I have never heard of someone who got 3d-acceleration really fast running 
with a pure 64-bit-system with ATI......

Thats a little bit information about the background, maybe other people this 
could help, too

Thanks for all your help !

best regards




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