Beetle PSX HW, slow internal FPS?

Libretro Cores
#1

Hi guys, I’m new here, so please don’t kill me if I’m asking something very basic.

For the last 10 years I’ve been using ePSXe, but only now I’ve discovered Beetle/Mednafen, so I have followed some guides and managed to configure Retroarch and Beetle PSX HW. Everything works and I really like this core/emulator.

However I see that games run a bit slow, or slower than I expected. In ePSXe I simply max out the Video/GPU configuration and I get a rock solid 50 FPS according to FPS counter. (I only PAL games). On Retroarch + Beetle PSX HW I get 49.5 FPS in the title bar, which sounds OK, but 24.92 in game. Both values stay stable on 99% of the time. Gran Turismo 2 here.

2017-07-23 17-45-35-RetroArch Beetle PSX HW 0.9.44.1 6ca001d __ FPS_ 49.5 __ Frames_ 768.jpg1283×768 494 KB

It’s believe it’s my hardware, I have a decent PC (i7 4770k, 16GB RAM, HD4950 3GB), and I tried different quality configurations, down to original PSX quality. I have a suspect this is an intended behaviour. Is there any way to unlock FPS here? Al least for me games feel way less fluid. Thank you in advance.

#2

The internal frames per second reflects the speed the game actually worked at . As long as you have stable 50 FPS (or 60 for NTSC) in the menubar, you should be all set.

There are some core options for overclocking, IIRC, and they might improve things a bit.

#3

I know overclocking just doesn’t work well with many games, including Gran Turismo 2, where things just go faster instead of being smoother. I’m not overclocking in ePSXe, and I believe i get real 50 fps, the game is very smooth there. EDIT: Just tested overclocking, nothing is changing at all.

#5

As for internal FPS, you are being confused here.

Gran Turismo 1 never ran at 60fps except for the ‘high-res night’ stages which drastically cut back on geometry complexity to achieve this. What you see in the ‘internal FPS’ is the internal framerate the PSX ran the game on. It’s just the way it is.

If ePSXe reports 60, that is certainly not reporting the ‘real’ internal framerate.

ePSXe may well have a way to run games at certain unlocked framerates, however, it might also be unsafe in general and result in various other glitches. What the overclocking feature in Beetle PSX does is - it removes ‘GTE / CPU’ stalls so that you can theoretically reach a higher framerate. This works in plenty of games and overall leads to a stabilization of framerate. It might not let you automatically overclock the entire game so that it runs at 60fps for every game, but it’s also a lot safer. As you might well know, a lot of games that were hardcoded at 30fps would never run properly at 60fps. This happens on PC too with games that are hardcoded to run at a specific resolution, try to run it at 60 by way of hijacking the framerate limiter, you might get broken physics, etc.

#6

Yes, I get this. But if I get GT2 running on ePSXe, it’s a lot more smooth. I can see there are more FPS there. And I’m not using any “hack” in ePSXe.

#7

Gran Turismo 2 never ran at those framerates, though.

If you are getting more than native framerates, it’s probably overclocking, and from what I’ve been told, overclocking in these other PSX emulators is not all that safe and can result in numerous glitches and issues.

Ours however is a more generalized, safer approach, but it doesn’t let you magically turn Gran Turismo from 30 into 60fps, as you are finding.

#8

Thanks for detailed explanation. ePSXe is not currently overclocking (CPU is set to 1x), and the video plugin is set to “auto detect FPS limit”, so at least in ePSXe 50FPS are standard (PAL). I understand however that ePSXe uses a different approach than Mednafen/Beetle, in fact the latter emulates a bit better GT2 compared to the former, wih less to no glitches. I’m also sure that GT2 never ran on the PS1 at more than 25/30 FPS, PS1 wasn’t a powerhouse and the game was really demanding. Since enabling CPU overclock didn’t make a difference for this core, I’ll live with the original 25 FPS. Thank you

#9

I’d recommend though that you use the US NTSC version when possible, PAL versions during the PS1 era were almost always 19.5% slower and had big borders.

#10

you must consider that mednafen is an “cycle accurate” emulator wich means that it will play games the closest posible to the real hardware, if a game has slowdowns during some scenes on a real ps1 it will play the same in mednafen. Thats why mednafen and xebra are the only emulators capable to play the bust a groove games, any other emulators just goes out of sync making them unplayable.

The cpu overclock option in the beetle psx cores is not the same as in epsxe and pcsx, it removes (at least for me) the slowdowns present on a game so the game mantains a constant framerate be it 15 20 or 30 fps.

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