I’ve tested all variants one more time, and here’re results:
(FX 6100 + RX 470):
(Win 10) (VSync: OFF)
1.7.10 190 fps
1.7.10 forge1614 177 fps
1.7.10 forge1614 opt_E7 201 fps
1.7.10 forge1614 opt_E7 GT6 2 fps
1.7.10 forge1614 GT6 2 fps
(Kubuntu 18.4) (VSync: ON) Don’t know how to turn off VSync
1.7.10 60+ fps
1.7.10 forge1614 60+ fps
1.7.10 forge1614 opt_E7 60+ fps
1.7.10 forge1614 opt_E7 GT6 54 fps
1.7.10 forge1614 GT6 14-44 fps
(Win 10)
1.12.2 forge2847 opt_F4 285 fps
1.12.2 forge2847 opt_F4 GT5 Community Edition 284 fps
(Win 10)
1.7.10 forge1340 GT5.07.07 IC827 20-30 fps
1.7.10 forge1340 GT5.07.07 IC827 opt_F4 25-35 fps
(Kubuntu 18.4)
1.7.10 forge1340 GT5.07.07 IC827 60+ fps
1.7.10 forge1340 GT5.07.07 IC827 opt_F4 60+ fps