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
