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. 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
