35" curved RPI3b+ retropie bad quality

[supebillen]

Asus vg35vq 35" curved monitor for vertical build.
Installed retropie image with emulation station quality looks bad do I need to change resolution?
Resolution of monitor are 3440x1440p 100hz how do I set the correct resolution so all picture fill the monitor. Have tried several images but they all look bad.
This my first experience with vertical image and monitor

[mitu]

You can change the resolution through config.txt parameters - see the Video Options parameters (hdmi_group/hdmi_mode).

The 3b+ may not support the - native - high resolution of the monitor so you may need to scale it down. To be honest, the monitor is a bit overkill for a Pi/playing old/retro games.

[supebillen]

@mitu said in 35" curved RPI3b+ retropie bad quality:

You can change the resolution through config.txt parameters - see the Video Options parameters (hdmi_group/hdmi_mode).

The 3b+ may not support the - native - high resolution of the monitor so you may need to scale it down. To be honest, the monitor is a bit overkill for a Pi/playing old/retro games.

@mitu thanks for answer.
I had this monitor anyway and was hooping to try it out before I build it ind an bartop. Only have an raspberry 3b+ on hand as the 4 is out of stock anywhere.
The monitor is 100hz but I know most games only runs 60fps.
Thanks for links to video options didn't know about the hdmi group mode options. I think this is what I am looking for but I am not able to finde correct hdmi_mode to use.
Can you help.
The asus monitor er in 3440x1440p 21:9 resolution. What do you think would be the best option?
Also the config.txt are modified on the SD card connected to the pc, right?
Or am I able to change the setting on the pi with USB keyboard connected to it?

[mitu]

@supebillen said in 35" curved RPI3b+ retropie bad quality:

The asus monitor er in 3440x1440p 21:9 resolution. What do you think would be the best option?

Depends on what video modes the monitor supports. Looking at the video modes in the docs, I don't see an out-of-the box mode with 21:9 aspect ration.
Try the settings from https://forums.raspberrypi.com/viewtopic.php?t=203100

Also the config.txt are modified on the SD card connected to the pc, right?

Yes, add the options at the end of the file.

[supebillen]

@mitu said in 35" curved RPI3b+ retropie bad quality:

@supebillen said in 35" curved RPI3b+ retropie bad quality:

The asus monitor er in 3440x1440p 21:9 resolution. What do you think would be the best option?

Depends on what video modes the monitor supports. Looking at the video modes in the docs, I don't see an out-of-the box mode with 21:9 aspect ration.
Try the settings from https://forums.raspberrypi.com/viewtopic.php?t=203100

Also the config.txt are modified on the SD card connected to the pc, right?

Yes, add the options at the end of the file.

OK,
Will try this when i come home to see if it boots up

display_rotate=2

disable_overscan=1
dtparam=audio=on
dtoverlay=disable-bt
dmi_cvt=3440 1440 50 7 0 0 1
max_framebuffer_width=3440
max_framebuffer_height=1440
framebuffer_width=3440
framebuffer_height=1440
hdmi_group=2
hdmi_mode=88
hdmi_aspect_21_9=7

#dtoverlay=vc4-fkms-v3d
max_framebuffers=2
gpu_mem=64
disable_splash=1