Try the altcoins section buddy. You will get a better answer there as no one mines BTC with graphics cards anymore.
I'll try over there thanks
I changed the driver now is going almost 23 goo improvement from 18.
I will look the video thanks, but I'm concerned about mod the bios, does reduce the longevity of the card and can I come back to the original bios once flashed ?
Your 23 ( I guess this is 23 Mh/s for ethereum) is OK for stock settings of an RX580 8GB card, but with BIOS mod you will get closer to 30 Mh/s.
The first thing to do, before modding the BIOS, is to save the BIOS currently in the card.
Backup your BIOS with ATI-Winflash https://www.techpowerup.com/download/ati-winflash/ (there is a version 2.74 but cant find it anymore).
Create new BIOS with Polaris BIOS editor https://github.com/jaschaknack/PolarisBiosEditor (use the 'one click' option)
Flash new BIOS with ATI-Winflash.
You may also need to then run pixelpatcher https://www.monitortests.com/forum/Thread-AMD-ATI-Pixel-Clock-Patcher.
More detailed tutorial here, https://anorak.tech/t/how-to-flash-a-amd-graphic-card-vbios/15
If you are running your card 24/7 for mining the updated BIOS will make little difference to the longevity of the card.
You can revert to the original BIOS, just flash the backed up original.
On some GPU cards there is a switch to select between 2 BIOS's , use one of the BIOS's for the flash mod, making sure to backup BOTH BIOS's.