Which custom resolution to choose for an Ultra Wide 2560x1080 monitor?

Question

linux

I got hold of a 25" LG 25UM58 monitor, the
video card is ancient - Radeon HD5450 Silent, supports only 4:3 5:4 16:9,
tried to set 2560x1080 = vidyuha does not export,

although xrandr seems that the card holds 8k ??? + extra 4"(๏̯͡๏)

~ $ xrandr
Screen 0: minimum 320 x 200, current 1680 x 720, maximum 8192 x 8192
......
Taking the maximum horizontal resolution that was visible in the settings,
I calculated the aspect ratio of 21:9

created 3*2 additional modes

#!/bin/bash

xrandr --newmode "1920x810_60.00"  127.50  1920 2024 2224 2528  810 813 823 841 -hsync +vsync
xrandr --newmode "1800x760_60.00"  110.75  1800 1888 2072 2344  760 763 773 790 -hsync +vsync
xrandr --newmode "1680x720_60.00"   97.50  1680 1760 1928 2176  720 723 733 748 -hsync +vsync

xrandr --newmode "1920x810_75.00"  162.75  1920 2040 2240 2560  810 813 823 848 -hsync +vsync
xrandr --newmode "1800x760_75.00"  142.75  1800 1912 2096 2392  760 763 773 796 -hsync +vsync
xrandr --newmode "1680x720_75.00"  125.75  1680 1776 1952 2224  720 723 733 755 -hsync +vsync

xrandr --addmode HDMI-0 1920x810_60.00
xrandr --addmode HDMI-0 1800x760_60.00
xrandr --addmode HDMI-0 1680x720_60.00

xrandr --addmode HDMI-0 1920x810_75.00
xrandr --addmode HDMI-0 1800x760_75.00
xrandr --addmode HDMI-0 1680x720_75.00

#xrandr --output HDMI-0 --mode 1920x810_60.00
#xrandr --output HDMI-0 --mode 1800x760_60.00
#xrandr --output HDMI-0 --mode 1680x720_60.00

#xrandr --output HDMI-0 --mode 1920x810_75.00
xrandr --output HDMI-0 --mode 1800x760_75.00
#xrandr --output HDMI-0 --mode 1800x720_75.00

and in the monitor itself, I turned on the fill mode, i.e. I stretched it to full screen,
there is practically no difference (I don’t play toys - I won’t say here).
Question: because vidyuha Silent, only for the sake of this I once took it,
probably there is no point in loading it if scaling works in the monitor itself,
or is it better to set it to 1920x810_75?
720p is enough for me to watch videos, and the card will heat up less,
I have only 3 coolers for the whole box:
1) PSU 2) Box CPU 3) I installed another one myself, on the chipset, (teared it from some old 478 or 775),
it works from 7 volts and does not buzz, + it stands at an angle of 45 ° and blows the vidyukha in one.
the temperature keeps about 50 < 60 C ° (although the box is standing near the battery and does not turn off for months)

PS
added 1800x760_75, on this I calmed down, you can of course use full HD 1920X1080,
BUT this is not buzzing >
if you do not turn off the fill mode in the monitor / scale, then the picture will be stretched,
if you turn it off, then unused areas will remain on the sides,
and this is (2560-1920) / (2560/100) = 25% of the screen (๏̯͡๏)

Answer 1

Well , the spec (Specs tab):
Accordingly, through 2xDVI or DisplayPort you can start the monitor at native resolution.
It may not be exported due to the small number of its operatives (ASUS set 512Mb, which is like death for UW).
For an unloaded mode, 50-60 ° is the norm for passive views.
It makes sense to blow the radiator of a video card with one valve only from the short side, so that cold air gets to the entire area; two can already be blown from the side of the lid, simultaneously frying the motherboard :)