Having some trouble with Shaders slowing down the emulation


I have a fairly decent system I think for emulation - it’s a Core 2 Quad with an Nvidia GeForce 8400 GS with 2GB of vram. Everything runs pretty fast and everything is working except this thing with the shaders.

I’m using the GL video driver and dsound audio driver. I’m running the current 205 mame core.

When I activate the crt-easymode shader (glsl) the game slows down to about 20 fps and the audio gets all broken. I’ve tried setting the sound driver to nul thinking maybe sound had something to do with it but the video is still slow. It looks like the shader is applied but everything is just really slow. If I turn the shader off everything goes back to normal.

Don’t even know where to begin to troubleshoot this. Let me know if there are logs I could post although being a performance thing there probably aren’t any errors.


It seems that’s just a very weak GPU, unfortunately. Benchmarks I found online indicate that it’s somewhere between Intel’s integrated HD 3000 (Sandy Bridge) and HD 4000 (Ivy Bridge) graphics.

That said, I would still expect it to be able to push crt-easymode, which is pretty lightweight, well enough. Do you have the MAME core’s “alternate render” core option enabled, by chance? If so, it messes up shaders.

Not that I know of unless it is on by default. I’ve got a pretty vanilla install of RetroArch at the moment… all I’ve done is change the input controls.

If we can tie it down to poor performing GPU I can for sure upgrade that - it was just a cheap card I had laying around and figured for emulation it would do the job.

Where do I check for that option? Is that in the core-options config file? Rich

Just checked and the alternate_renderer is disabled. Can this be seen in the interface somewhere just to confirm that it’s reading the proper config file? Rich

Alright, you’re probably good, then. You can check in the quick menu > options menu. Some other shaders to try would be zfast-crt and crt-pi. If it can’t get either of them full speed, there’s probably something amiss.

Both of those shaders seem to work okay so then it’s probably an issue with that graphics card then? Sounds like I may want a video card a little more powerful… any recommendations on a low profile card that won’t break the bank? Rich

Yeah, sounds like your GPU is just a bit weak.

That really depends on what you’re thinking of as affordable. For $100-150, you can get a radeon 560 or an nvidia 1050, either of which should be a big step up.

Question is do you think the CPU is sufficient? I guess that depends also on what I want to emulate but I was hoping to be able to run Wii games on Dolphin.

I’m considering building a Ryzen 2200g based micro ITX for my cabinet but haven’t quite got the funding for it yet :wink: - mainly just trying to get software all set. Thinking the built in gpu for that would work fairly well.

Thank you so much for your help.

I’m not sure if that CPU is enough for dolphin or not. It’d be borderline at best, I think.

I’ve been thinking of doing a similar Ryzen build, myself, and yeah, the integrated GPUs on those is comparable to a Radeon 7770, which should be plenty.

Watched an ETA Prime video where he built a system with a Ryzen 2200g and it was handling about whatever he wanted to throw at it so figured that would be a pretty good way to go.

I priced it out and looks like I could do it for somewhere around $300 since I don’t need an HDD or case. Helps to have the GPU built in. At that price it’s not worth even messing with this older system.


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Is my system too dated to run shaders at high resolution? I’ve got an i5-4590 with a gtx 970. Shaders and PGXP seem to be too much for my system to handle. Am I doing something wrong? My only renderer options are hardware or software.

GTX 970 should be able to handle most stuff. However, if you’re using a higher internal resolution and then putting a shader over the top, that’s going to be very demanding as the shader has to be applied to the entire giant image.

So 4x might be too much? What about for a gtx 1080?

epsxe works great but it doesn’t have pgxp, unfortunately.

Which shader(s) are you running on top, if any?

The MJ cell shader presets. On epsxe I use the cartoon shaders, which only need 1 or 2 passes to look really good. Do you think I could apply those shaders with beetle?

They would have to be ported to RetroArch’s shader format. If you can link me to them, I can take a look.

Does this work? There are several but I couldn’t upload them from my hard drive. This is probably the one I use

I meant to give just this link, sorry. http://www.mediafire.com/file/6kcdwb17jn3cxdy/Carsha.rar

I’m also curious to know why I can’t change my renderer to vulkan.