Im having some massive lag with my RX 580 8GB, i try everything to fix this, there's something that i can do?

This issue was resolved in 3.1.0. It is unclear what version you are running as you have not told us, and you have modified the version of Forge - which will cause crashes and issues if this install is based on 3.0.8.

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Version 3.1.2

Okay - try this anyway:

certain RX and Vega cards seem to have a problem with a foamfix tweak (on 3.0.8) you can try this:
in: .\SevTech Ages\config\foamfix.cfg
under texures, set I:fasterAnimation=0

If that doesn't help, please try without Optifine and without modifying the pack.