Custom Resolution Utility (CRU)

[Nodens]

(11-14-2023 01:55 AM)ToastyX Wrote:  It is monitor behavior controlled by the firmware. The problem is the monitor is not supposed to disconnect when sleeping, and it shouldn't be slow to wake up. This is a flaw in the monitor, not something you can change unless you can edit the firmware somehow.

I was afraid this may be the case. The monitors we're talking about are 2x Samsung Odyssey G7 32" (SKU: LC32G75TQSUXEN).

Quote:I think you're getting confused because you saw DPMS has four power states with one coincidentally described as deep sleep, but DPMS is an old standard that was deprecated 20 years ago and replaced by DPM, which only has two power states: on and off (sleep/standby). Windows only implements those two power states, so the power state information in the EDID isn't relevant.

Basically I was looking at page 110 of the DP 1.2 spec document. Where it describes:

Code:

In D0 state, a Sink device may disable DP_PWR
– Sink device is OFF (or reset) or not monitoring Source Detection signal
– Sink device de-asserts HPD signal
– Sink device may go to D1 state any time
– Sink device may go to D0’ state if it supports Source Detect feature and Source device is not
detected
• In D0’ state, a Sink device must enable DP_PWR (For a tethered Sink device, upon detecting
DP_PWR Consumer)
– Sink device de-asserts HPD signal, but monitors Source Detect status
– Sink device goes to D1 when Source detected
• Sink device may go to D0 state any time
• In D1 and D2 states, a Sink device must enable DP_PWR (For a tethered Sink device, upon detecting
DP_PWR Consumer)
– Sink device asserts HPD signal
– Sink device is either receiving or ready to receive bits over Main Link
– Sink device goes to D0’ state when Source is absent
– Sink device stays in D1 even when Source writes 2 to Address 600h
• Sink device may go to D0 state any

Quote:The issue you're having with the monitor is unrelated to power states. It's a design issue with the monitor also complicated by the way DisplayPort works. VGA, DVI, and HDMI use DDC, and DDC is powered by the source so the EDID can be read even if the monitor is turned off. DisplayPort monitors basically emulate DDC through the AUX channel, which disconnects when the monitor is turned off, but most monitors will stay connected while sleeping. The "deep sleep" option you talked about is a setting some monitors offer to use less power while sleeping, but it has the side effect of disconnecting as if the monitor were turned off.

Is this not the mechanism described above? That in D0 the monitor is allowed to do that according to spec? Or I'm reading that wrong? (The spec is huge so I'm searching through parts that seem related at his point).

Quote: I guess you are saying your monitor does that with no option to disable that behavior.

Yes this is exactly what it does. According to my research most monitors that exhibit this behavior have an OSD option to toggle it. These monitors do not.

(11-13-2023 11:44 PM)Nodens Wrote:  You didn't say what side effects you're seeing, but issues like windows resizing or moving to another monitor or hearing the device disconnect/reconnect sounds are side effects of Windows responding to the monitor disconnecting. So yes, emulating the EDID so Windows thinks the monitor is always there will work around those issues.

Indeed I neglected that, my bad. The 2 main issues I am experiencing are these:

1) When monitors go to sleep they need about 8-12 seconds in order to wake up and they do what looks like a "double" wake up (blanking and re-initializing), the second one being shorter, which results in like 12-15 seconds total delay. Initially I didn't mind this but it has started being extremely annoying specially when I'm in a hurry and I have to wait for the monitors in order to eg send that email I almost forgot while I'm already late for an appointment. Also depending on the Nvidia driver sometimes this results in a weird error involving explorer.exe (maximized windows not factoring the taskbar on the the Y axis and the bottom of the maximized window landing behind it) or, extremely rarely, re-arranged desktop icons (I have a workaround for that so this is the least of my worries).

2) The second monitor, that is on my left side is also connected to my homelab Fedora server, which I usually administrate headless via ssh but sometimes I need to do things there that are *much* faster with a GUI (eg diffing big configuration files with Kompare). If I have the monitor on the HDMI and it goes on sleep while I work on my workstation on the main monitor, when it wakes up it does so *much* faster, not doing the second wake (no blanking and reinit--a total of 4-5sec), BUT causes the main monitor to do it instead. I assume this is also related to the monitor's deep sleep behavior as I think it triggers HPD on the the DP port as well, on wake, which in turn triggers a PNP re-detection in Windows.

I really like these monitors in general but this behavior has gotten extremely old in a year of using them.