Games are sometimes laggy and audio is distorted retro pie

[Malman35]

I recently have been working on my retro pie project in which I am using the adafruit 2.8" tft screen https://www.adafruit.com/products/1601 with the pocket pigrrl img https://learn.adafruit.com/pocket-pigrrl/software-1
And I was able to add some games (nes, sega genesis, gb) and some worked okay like Mario land (Game boy) but when I tried to play sonic 1 (I tried sonic 2 as well which had the same result) it was sloooooowwwww! the sound was bad sounding and I felt like I was playing in 4x slow motion! also some nes games worked okay but at times the audio was kinda bad sounding and one game was like sonic in that it was slow with bad sounding audio but the problem only started after I started pressing buttons (for those curious it was Afterburner 2)
Why is this happening? I am using a rpi 1 b+. Is the b+ not capable enough? I would really appreciate some help here. Thx for your time.

[Vanfanel]

The Raspberry Pi B+ CPU won't cope with the Genesis Plus GX libretro core, which your distro must be using.
Genesis Plus GX is a 100% accurate Sega Mega Drive and Master System emulator, so it takes a certain amount of CPU power to work.
You can use the arm-optimized PicoDrive core, but it's far less accurate. I wouldn't use it anymore.

You can, however, emulate the Sega Master System using the accurate Genesis Plus GX, and forget about the Mega Drive until you get a Pi2/3.
There are great games on the Master System and, if the core has been compiled with the right defines, it should be using ~50% of the CPU on the Pi1,

[Malman35]

The Raspberry Pi B+ CPU won't cope with the Genesis Plus GX libretro core, which your distro must be using.
Genesis Plus GX is a 100% accurate Sega Mega Drive and Master System emulator, so it takes a certain amount of CPU power to work.
You can use the arm-optimized PicoDrive core, but it's far less accurate. I wouldn't use it anymore.

You can, however, emulate the Sega Master System using the accurate Genesis Plus GX, and forget about the Mega Drive until you get a Pi2/3.
There are great games on the Master System and, if the core has been compiled with the right defines, it should be using ~50% of the CPU on the Pi1,

hi Vanfanel,
Thanks for that explanation. I was able to find sonic 1 and 2 for the master system and it works great on there. One more thing most NES games work okay but some NES games seem to be laggy. Mario 3 wasn't that bad but it started to lag a little at times and afterburner was quite laggy. I was trying some SNES games and Mario world seemed okay from what I could tell but super Mario kart was like slow motion 2x! Oh don't know if this is relevant but my rpi is overclocked to medium

[Vanfanel]

Use the fceumm Libretro/Retroarch core instead of the Nestopia core, overclock you Pi-1 to 1GHz, and you will have every NES game running smooth

[Malman35]

Use the fceumm Libretro/Retroarch core instead of the Nestopia core, overclock you Pi-1 to 1GHz, and you will have every NES game running smooth

okay so I know how to overclock but I am not sure how to change/use the fceumm Libretro/Retroarch core instead of the Nestopia core. Could you please tell me how too? Thank you for the help!

[Malman35]

overclock you Pi-1 to 1GHz

Since that was the one thing that I understood how to do I went ahead and tried it. I selected the Turbo mode which was a 1GHz. When it booted back up everything was kinded of slanted kinda like this and kept flickering and when I tried to play a game it was a mess! So I turned it to high (which is 900MHz I think) and I didn't get that weirdness but the games had the same problems as before.
Just thought I should let you know about this.

[Malman35]

I figured it out. If I turn off the shader in retroarch.cfg then for the most part all games run smoothly.