How to force monitor to lower refresh rate to 30hz

[ezcapper]

I want to lower the refresh rate on my laptop monitor to 30 hz. Because with vsync on it will force the frame rate to 30 fps, making it smoother and less cpu intensive to capture the screen with obs. I have intel hd graphics and when I try to add a 1280x720 resolution with a refresh rate of 30 hz, it says something like it's out of the maximum bandwidth range. I tried the command line program QRes, but it says it is not valid. Any ideas? Thanks.

[Cornucopia]

Refresh should NEVER, I repeat NEVER go below ~48Hz, or it will exhibit noticeable if not objectionable flicker.

Moot point, as AFAIK no modern LCD screens refresh less than 50Hz.

What you are asking IS out of bandwidth, but actually on the low side.

Scott

[ezcapper]

I've recorded with my hdtv as my monitor at 24hz, the tv confirms the setting. It allows 23hz and 24hz, but not 30. There is no flickering.

[pandy]

Refresh should NEVER, I repeat NEVER go below ~48Hz, or it will exhibit noticeable if not objectionable flicker.

Moot point, as AFAIK no modern LCD screens refresh less than 50Hz.

What you are asking IS out of bandwidth, but actually on the low side.

Scott

This is valid for CRT but for systems with memory (such as PDP or LCD) is not correct.
Refresh rate can go even to fraction of Hz.
Some notebooks use lower refresh rates to reduce power consumption.

[pandy]

I want to lower the refresh rate on my laptop monitor to 30 hz. Because with vsync on it will force the frame rate to 30 fps, making it smoother and less cpu intensive to capture the screen with obs. I have intel hd graphics and when I try to add a 1280x720 resolution with a refresh rate of 30 hz, it says something like it's out of the maximum bandwidth range. I tried the command line program QRes, but it says it is not valid. Any ideas? Thanks.

This is highly related to firmware on LCD controller - if input frequencies are out of embedded range then you will receive message about incorrect frequencies - only one way to solve this is firmware modification - beyond normal user capabilities...

[ezcapper]

Here is how I was able to do it. I confirmed that my refresh rate was 30 hz using browser tests. Also, recording with obs is alot smoother now. See picture. My OS is linux mint.

the -Vsync at the beginning is really +Vsync, the picture got cut off. You might have figured this out from the next command.
I record to mjpeg in OBS with video bitrate set to 30,000. Also, I set the OBS scaled resolution to the same as the base resolution: 1280x720. It feels like the recordings are just as good as the real time screen action. It is hard to tell which is which. No flickering or any weird things. Very cool!