Frame stuttering

Libretro Lakka
#1

I’m suffering from frame stutter on the emulator cores on Lakka using a Dell Optiplex 380. Here are the detailed specs:

Pentium Dual Core E5800 3.20GHz 64-bit 2GB DDR2 RAM ATI Radeon HD 4550 512MB GDDR3 PCI Express x16 Video Card

Vsync is off, otherwise I’d get graphical glitches in the menu and in gameplay. The frame rate improves if I lower the resolution from 1080p to 1280x720 (720p), however it’s still not perfectly smooth. I don’t get it, I’m getting perfect frame rate on SNES/NES/Genesis and all other older console emulators on my Wii but not on this PC with lakka.

I’d like to get a GeForce GT 730 2GB DDR3 PCI Express x16 to see if it’ll improve things, it’s within my budget and I don’t want to spend too much on my 2nd PC…

but I want to be sure - Will a decent video card improve the frame rate for the emulators on Lakka?

#2

Are you using any shaders? My guess is yes, if changing your resolution helps your framerate. In that case, yes, getting a better GPU should resolve it.

#3

Nope, not using any shaders. I just use the HW bilinear filter. But thanks for the advice, I guess I will buy that GeForce GT 730 video card then. I figured it would help, the HD 4550 is pretty dated and only has 512MB GDDR3 64-bit memory.

#4

Hmm. If you’re not using any shaders, it shouldn’t be taxing your GPU just to scale it up. Bilinear scaling up to 1080p shouldn’t be any less performant than 720p. Are you using the OpenGL video driver?

#5

I’m not sure. How do I use it?

#6

go to settings > driver and make sure the video driver is set to ‘gl’. It’s the default, so I would assume that’s what you’re using if you haven’t changed it.

That in mind, I’m not sure what would be causing the framerate dips at higher resolution and thus can’t guarantee that a new GPU will fix it, but it seems at least likely to help.

EDIT: when it stutters, is the audio affected, in the form of crackles? If not, hold off on the GPU and lets try to resolve your vsync issue. Try turning vsync on and audio sync off and see if that helps at all.

#7

I don’t get any audio crackling. I tried what you suggested but still didn’t fix it. Whenever I turn on Vsync and quit retroarch to restart it, there’s always this black line in the middle of the screen in the menu that blinks very fast. It goes away when I turn Vsync off and quit retroarch to restart it.

#8

N64, PS1 and PSP games all run great but I’m used to emulators for those consoles not running perfect, what I want is smooth 60fps on the older console emulators.

#9

if you’re not getting audio crackles, it’s not an issue with your framerate dropping, but rather an issue with vsync. If you can’t turn on vsync, if you go to settings > frame throttle, is your maximum run speed set to 1.0x?

#10

Holy crap that fixed it. The frame throttle was set to 0 so I did what you said and set it to 1.0x and then turned vsync back on. Now it has no glitching and the emulators run smoothly without any frame stuttering at 1080p! Thank you very much!!!

This not only saves me the hassle and money of buying a new video card to see if it would fix the problem, but I like the Radeon HD 4550 I’m currently using because it has S-Video output. I want to keep the option of being able to connect this to my CRT TV.

#11

Ah, sweet. Glad that got you fixed up :smiley:

One thing to know: setting the max run speed to 1.0x makes you unable to fast-forward (since FF is just disabling vsync and letting it run ahead). Probably not a big deal but wanted to save you any future confusion it might cause.

#12

Ah ok, thanks for letting me know. I’ve never used fast-forward before on retroarch and don’t even know how to, so not a big deal. I don’t really need it anyway. Thanks again