Following this : reddit/r/linux_gaming/comments/hqlsrp/is_there_a_way_to_overclock_my_monitor_and_extend/, I did:
$ cvt 1920 1080 75
# 1920x1080 74.91 Hz (CVT 2.07M9) hsync: 84.64 kHz; pclk: 220.75 MHz
Modeline "1920x1080_75.00" 220.75 1920 2064 2264 2608 1080 1083 1088 1130 -hsync +vsync
$ xrandr --newmode "1920x1080_75.00" 220.75 1920 2064 2264 2608 1080 1083 1088 1130 -hsync +vsync
$ xrandr --addmode HDMI-0 "1920x1080_75.00"
X Error of failed request: BadMatch (invalid parameter attributes)
Major opcode of failed request: 140 (RANDR)
Minor opcode of failed request: 18 (RRAddOutputMode)
Serial number of failed request: 35
Current serial number in output stream: 36
I found someone who had the same issue as me forum.manjaro/t/monitor-overclocking/30100/2, but unfortunately he never came back to answer people asking for more information…
Here pastebin/1tRfw1aB are information that were asked on that post.
So, what is the xrandr error caused by?
Edit : I get the same error with 30 Hz.
This depends heavily on what your hardware can actually do. Does both your GPU and monitor support these higher refresh rates?
The reddit post is about FreeSync. Do you use FreeSync? (Or any other fancy marketing name which is basically the same?)
Is your monitor connect via DisplayPort? (From your log, I suspect not.)
How to know if they support it?
I don’t use FreeSync, I don’t know what it is.
My monitor is connected through HDMI, and the HDMI port is v 2.0b.
By using search engines and researching yourself…
Not every monitor can be overclocked. Some 60hz monitors can be overclocked to 75hz (sometimes only a number between 61 & 74hz), some 144hz monitors can be overclocked to 165hz, but not all of them. You have to research it. Some monitors have the overclock built into it’s own settings (OC Mode) that you can use as well.
IMO, unless your monitor specifically supports overclocking, I don’t recommend the hassle… I’ve dealt with it a lot years ago on both Windows & Linux. 1 monitor was only able to overclock to 67hz (after many many tries to find it), and the other was 75hz (which was fine), and the other one was 71hz. I ended up reverting all but the 75hz back to 60hz.
Though now I run a 144hz, 60hz, and 60hz monitors.