[ltp] Rovclock and Dynamicclocks / Rovclock and T40p

[Alex Deucher]

On 1/29/06, Michael Stilkerich <ms@mike2k.de> wrote:
> Hi,
>
> I just discovered the rovclock page of thinkwiki and have two questions
> regarding that tool:
>
> (1) Does anybody here use it on a T40p and can tell me safe values for
> underclocking? My Mobility FireGL 9000 comes with 200 MHz memory clock
> and 252 MHz gpu clock. Especially the memory clock seems very sensible to
> underclocking, which makes artifacts appear on the screen.
>
> (2) The Wiki page says rovclock and DynamicClocks of the radeon driver
> complement each other. In my understanding, rovclock can be used to stati=
cally
> set the clock of gpu clock and memory whereas DynamicClocks does this dep=
ending
> on the actual load. DynamicClocks would therefore interfere with rovclock=
, since
> it would overwrite changes made by rovclock. Practically the values set v=
ia
> rovclock don't seem to be changed by DynamicClocks (according to rovclock=
 -i),
> so could anyone here explain the difference of the two to me?

DynamicClocks doesn't change the clocks itself, it just sets the clock
related registers to dymanic mode.  the HW itself takes care of the
scaling.  I'm not too familiar with rovclock, but if it just sets the
clocks to a fixed frequency, then that will potentially override the
settings from DynamicClocks.  I haven't looked at the source to
rovclock, but it may leave the dynamic stuff on (if you enabled
DynamicClocks) which may or may not cause a problem.

Alex

>
> Thank you,
> -Mike
> --