When I start any game which uses DOSBOS for compatibility my monitor shuts off into low power state and will not wake up requiring a press of the reset button. For illustration I've been trying to play Star Trek: 25th Anniversary and when i start the game via menu icon or terminal it exhibits the above action. I've tracked it down to "fullresolution=original" in the dosbox_st25.conf . I had to change it from "original" to my monitor's native resolution, no other changes were needed for it to work.. This fixes the problem but is a pain to do for every game which uses DOSBOX.

My system/Hardware is as below.

Processor Information:
CPU Vendor: GenuineIntel
CPU Brand: Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz
CPU Family: 0x6
CPU Model: 0x9e
CPU Stepping: 0xc
CPU Type: 0x0
Speed: 5100 Mhz
16 logical processors
8 physical processors
HyperThreading: Supported
FCMOV: Supported
SSE2: Supported
SSE3: Supported
SSSE3: Supported
SSE4a: Unsupported
SSE41: Supported
SSE42: Supported
AES: Supported
AVX: Supported
AVX2: Unsupported
AVX512F: Unsupported
AVX512PF: Unsupported
AVX512ER: Unsupported
AVX512CD: Unsupported
AVX512VNNI: Unsupported
SHA: Unsupported
CMPXCHG16B: Supported
LAHF/SAHF: Supported
PrefetchW: Unsupported

Operating System Version:
"Fedora release 31 (Thirty One)" (64 bit)
Kernel Name: Linux
Kernel Version: 5.3.16-300.fc31.x86_64
X Server Vendor: Fedora Project
X Server Release: 12006000
X Window Manager: GNOME Shell

Video Card:
Driver: X.Org AMD Radeon VII (VEGA20, DRM 3.33.0, 5.3.16-300.fc31.x86_64, LLVM 9.0.0)
Driver Version: 4.5 (Compatibility Profile) Mesa 19.2.8
OpenGL Version: 4.5
Desktop Color Depth: 24 bits per pixel
Monitor Refresh Rate: 143 Hz
VendorID: 0x1002
DeviceID: 0x66af
Revision Not Detected
Number of Monitors: 2
Number of Logical Video Cards: 1
Primary Display Resolution: 2560 x 1440
Desktop Resolution: 5120 x 1440
Primary Display Size: 23.54" x 13.23" (26.97" diag)
59.8cm x 33.6cm (68.5cm diag)
Primary VRAM: 16384 MB

Sound card:
Audio device: Realtek ALC892

Memory:
RAM: 64189 Mb

Miscellaneous:
UI Language: English
LANG: en_US.UTF-8
Total Hard Disk Space Available: 431459 Mb
Largest Free Hard Disk Block: 48159 Mb

This popped out at me. 2 monitors.
DOSBox isn't really built for multi-monitor support.

Thinking you need to check what is configured as the primary monitor on your fedora install, and adjust that.
-DOSBox might be trying to run on the other monitor your system has, and whatever Radeon GPU linux drivers you have installed are auto low-powering the other monitor off.
Try resetting which the primary monitor is on your system.
Fullscreen DOSBOX across multiple monitors is probably still a pipe-dream.

If you are not using a CRT then you really shouldn't be using "original" anyway. This is still the default in DOSBox for compatibility reasons but may possibly be changed in the future since most DOSBox users do not have a CRT.. Use your desktop resolution for now.

There is possibly a bug in SDL 1.2 with multiple monitors and with 0x0 or desktop using both monitors instead of just one or perhaps it's a combination of an SDL bug and 4:3 resolutions being stretched, see reddit thread below.. It's on my list of things to backport from SDL2 until the official version of DOSBox switches to SDL 2 which will break <XP support. :(

It's also possible that your monitor doesn't support the resolution DOSBox is trying to set when "original" is used so it may be trying to switch to 320x200/320x240 and I'm not sure what the current state of video driver scaling is on Linux

Also
https://www.reddit.com/r/emulation/comments/7kfa86/scummvm_20_has_been_released/drewr16/

As stated above, check the other monitor, the display may well be there.

If not, then SDL has probably picked a screen mode that is available, but what the monitor does not support. Contrary to what is stated above, I believe that if you have scaler=normal2x under [render] and the game is 320x200, fullresolution=original asks SDL for a screenmode best suited for 640x400, unless aspect=true, in which case I think it will ask for something best suited for 640x480. I seem to remember that the best-suited code picks the smallest available resolution that fits what is asked for.

If xrandr lists 640x480, SDL is likelly to pick that, and it's very possible that your monitor can't really display it. Perhaps if you set scaler=normal3x it would look for 960x720 and switch to a screenmode that fits that? If that works, the problem becomes "why is there a non-functional 640x480 mode available".

OP, are you still alive?