Hello I have a Dell T3600 with a Xeon E5-1603, 16gb ram, and a RX 570.
I run Regular non modded Minecraft 1.12.2 and 1.14.4 and I receive around the 100 fps mark with high settings and mipmap level 4.
With Modded Minecraft 1.12.2 I get 1 fps on high settings and mipmap 4 but I get 60 but not very stable fps at everything on low and mipmap off.
I ran hwmonitor and when running non modded minecraft it was clocking to about 818MHz but when in modded minecraft it clocked to 741MHz. It did run at 1200MHz on 1.14.4.
Any ideas? Thank You!