Desktop Resolution Issue - 15 FPS performance

RetroArch Windows devices
#1

I am new to retroarch on the PC. It’s a very powerful front end. But there is a tough learning curve!

So, sorry if this is a stupid question. But I am using retroarch on a PC connected to a 4K monitor with a 4K desktop screen resolution.

Games run 2 to 4 times slower than normal by default (15 FPS with shader and overlay or 30 FPS with shader only). After a lot of messing around with sync options. I think the problem is actually simple and not a sync issue at all… the desktop resolution is too high. If I manually change the desktop resolution to 1080p then run Retroarch I get games running at 60 FPS and so they play at normal speed with shader and overlay .

Is there a way of getting retroarch to switch my desktop resolution to 1080p when it starts up? Based on a google search I changed the parameters…

video_fullscreen_x = “1920” video_fullscreen_y = “1080”

However the game still ran at a terrible speed. So I don’t think Retroarch changed the desktop resolution at all when it started up.

p.s. I also have the common problem that I can’t get the genesis_plus_gx core to work and no other sega core is listed when I go to download. My genesis roms files are .smd. My master system files are .sms. When I run a genesis rom I get a black permanent screen. When I run a master system rom the window closes straight away. All the other system cores I have tried run A OK . Any ideas on that one?

#2

Given the listed symptoms, here are a few questions:

What’s your video hardware? Which video driver are you using? (GL, Vulkan, DXD9, DXD12…) What type of shaders are you using? (Cg, GLSL, Slang?)

#3

Sorry but I have no idea what video drivers retroach uses. I haven’t manually changed any video driver settings. On installation I think Retroarch tried to install dx9. But it failed as I already had a newer version of direct x and stated the install was not required.

The shader I am using is crt-easymode-halation.glslp

If I can get retroarch to switch the screen resolution to 1080p then all is good as I get 60FPS. It’s just a pain to do it by hand every time I want to play instead of work.

#4

This little, wonderful app will help. It allows you to create a shortcut for any app that will make it start at any resolution you want, and it will revert to your desktop resolution once said app is closed.

http://www.bcheck.net/apps/reso.htm

#5

Thats a great little app ! Works a treat ! Thanks a lot

#6

Yeah : ) I use it aaaaall the time to run emulators at custom resolutions and aspect ratios. It is extremely useful, and not very well known.

Regarding your video driver, it’s super simple to check/change. Config tab > driver. Considering your shader extension, it’s most likely gl anyway.

retroarch%202018-09-07%2004-56-15
retroarch 2018-09-07 04-56-15.jpg1280×720 236 KB

And lastly, genesis plus works great… try updating it. I recommend using various instances by the way, since it runs games from very different platforms that require their own settings and shaders to look and play properly, and configuring each game separately is a royal pain in the lower back. I use one for gg, another one for sms and yet another one for megadrive/megacd. There’s also the picodrive core, which emulates md/32x/mcd very well. I use it for 32x. If for whatever reason you are having trouble updating and downloading cores in-app, here are the latest win64 (I asssume that’s what your pc is based on) versions

http://buildbot.libretro.com/nightly/windows/x86_64/latest/