Am 13.01.23 um 16:09 schrieb Alex Deucher:
On Fri, Jan 13, 2023 at 10:05 AM Braiam <braiamp@xxxxxxxxx> wrote:
AMD RX 590. Forgot to include it. How do I know the blanking period?
OK polaris falls into the first bucket. Look at the full modelines.
E.g., xrandr --verbose.
Would variable refresh rate mess up with that?
Probably.
Totally, as far as I know VRR is currently a complete show stopper for
reclocking the MCLK.
But on the other hand VRR could potentially be used to artificially
create some overlapping VBLANK period to do the actually reclocking.
Interesting idea.
We might want to ping Harry or somebody else form the DC team if they
have thought about that yet.
Christian.
Alex
On Fri, Jan 13, 2023 at 10:57 AM Alex Deucher <alexdeucher@xxxxxxxxx> wrote:
On Fri, Jan 13, 2023 at 9:47 AM Braiam <braiamp@xxxxxxxxx> wrote:
Hi,
I have two monitors with the current following configuration:
Screen 0: minimum 320 x 200, current 5120 x 1440, maximum 16384 x 16384
DisplayPort-0 connected primary 2560x1440+0+0 (normal left inverted
right x axis y axis) 597mm x 336mm
2560x1440 164.83 + 59.95 + 120.05* 96.01 72.01 60.01
143.97 120.00 74.97
[snip]
DisplayPort-1 connected 2560x1440+2560+0 (normal left inverted right x
axis y axis) 597mm x 336mm
2560x1440 165.00 + 59.95 + 120.06* 96.04 72.01 60.01
50.01 48.01 144.00 119.99 99.99
[snip]
HDMI-A-0 disconnected (normal left inverted right x axis y axis)
HDMI-A-1 disconnected (normal left inverted right x axis y axis)
DVI-D-0 disconnected (normal left inverted right x axis y axis)
The pp_profile_mode:
NUM MODE_NAME SCLK_UP_HYST SCLK_DOWN_HYST
SCLK_ACTIVE_LEVEL MCLK_UP_HYST MCLK_DOWN_HYST MCLK_ACTIVE_LEVEL
0 BOOTUP_DEFAULT: - - -
- - -
1 3D_FULL_SCREEN *: 0 100 30
10 60 25
2 POWER_SAVING: 10 0 30
- - -
3 VIDEO: - - -
10 16 31
4 VR: 0 11 50
0 100 10
5 COMPUTE: 0 5 30
- - -
6 CUSTOM: - - -
- - -
I have set their refresh rate to 72.01 which is a mode equal for both,
and the MCLK wasn't downclocked either. They are branded HP and
Scepter. Using a vtty doesn't help either.
Is having the exact same monitor really required? If not, how can I
check what is causing
the memory clock to be pegged that high?
It depends what GPU you have. Older ones can only reclock memory
during the vertical blanking period assuming it's long enough as the
whole reclocking process takes a certain amount of time. If it
doesn't happen during the blanking period you will get visible
glitches on the screen when the reclock happens. If the vertical
blanking period is not long enough or if the vblank periods are not
aligned when using multiple monitors, the driver doesn't reclock. The
mode lines (not just the refresh rate) have to be the exact same for
the vblanks to line up when using multiple monitors. Your best bet is
to take the mode line you want to use from one monitor and apply it to
the other monitor. Newer GPUs have more flexibility and can reclock
memory in more situations, but there are still some monitors where the
timing may not work out.
What GPU do you have?
Alex
--
Braiam
