These new blocks, such as technology mods, often use up more computer resources than your typical Vanilla Minecraft blocks. However, when it comes to Modded Minecraft there is MUCH more content provided in-game than normal Minecraft. After all, that is rarely the case in Vanilla Minecraft or normal servers. This is completely understandable, as is believing that how you build will not impact others. If you are new to the modding realm, you may not be as experienced with the difference between 'efficient' and 'inefficient' systems when using technology and such in Modded Minecraft. Minimizing Lag Guide - For Players Introduction
This topic applies to all modpacks, not just this particular modpack and while this modpack does make an effort to minimize lag out of the box- not all lag can be minimized by modpack configurations alone. In general, most lag is caused by chunk generation, chunk loaders (with machines and such in the loaded chunks), or players creating inefficient builds/systems that can cause major lag or/and issues. Both the server owner and players have a responsibility to minimize lag as much as possible on modded Minecraft.
