I have an embedded Atom E3825 board where the BIOS can set for LVDS a minimum of 800x480, while my display is a 640x480 one. Can I set it to the lower resolution anyway? How to?
I tried with cvt
and xrandr
but the former can just figure that 800 pixels wide is the physical limit, and the latter can't set timings (if I understood the limits).
In fact asking
~# cvt 640 480
# 640x480 59.38 Hz (CVT 0.31M3) hsync: 29.69 kHz; pclk: 23.75 MHz
Modeline "640x480_60.00" 23.75 640 664 720 800 480 483 487 500 -hsync +vsync
and trying
xrandr --newmode "640x480_60.00" 23.75 640 664 720 800 480 483 487 500 -hsync +vsync
xrandr --output eDP1 --mode 640x480_60.00
what I get is just an unreadable shrunk screen.