Hello all thanks for answers !
https://archive.recalbox.com/ downloaded the rpi3 version good link its hard to fail this.
When I launched the rpi it said 18.07.13 all working well except "playing".
After the download I used echter.
Its a sandisk 32gb class 10 : https://www.amazon.com/Sandisk-Ultra-Micro-UHS-I-Adapter/dp/B073JWXGNT/ref=sr_1_4?ie=UTF8&qid=1541535814&sr=8-4&keywords=sandisk+32gb++class+10&dpID=41o%252BsCWxP2L&preST=SY300_QL70&dpSrc=srch
Please note I tried on odroid which is the same process I think, and I didnt meet any problem.

Hello I am using recalbox last version on Raspberry Pi 3B v1.2.
And its unplayable all my actions on controller are done slowly.
For example on MarioWorld (super nintendo) when I press jump mario jumps like 1 second after I pressed the button.
I thought it was the controller so I tried it on my odroid xu4 and it works perfectly and its the same on my computer with the same rom.
I don't get why it doesnt seem that the rpi is at 100% usage cause except my action all is displayed correctly.
I activated FPS monitor and I run near 60fps every time.
So I don't know what can I do ?
Thanks for your help