Hi, i'm not sure if this is the right place to post this but I need some help. I couldn't find anyone with a similar problem after a long time googling and, nowhere that i found this seems to be documented in vanilla minecraft or tekkit or anything else. Issue is at the bottom after verbose explanation I started playing legends a couple days ago and my world is still very new. I don't know how most of the mods work so I havent begun to build much. I used technic years ago so i'm still pretty familiar with EE2/IC2/Buildcraft but nothing else. So far my world is just a tiny house, a small logistics pipe+energy condenser setup to make low voltage solar arrays automatically and a 64X64X64 Iron block building that isnt done yet that will serve as my mega factory that I will be building railcraft and IC2 stuff In, once I figure out what everything in railcraft is for. (I want to use tank carts to bring oil to me so I can start with more advanced Buildcraft stuff) My PC specs are fine gtx 980 2-way SLI rampage 4 black edition mobo i7 4930k 16GB DDR3 2400 etc etc, basically, i should be able to run a thousand copies of minecraft simultaneously. I have a constant and stable 144FPS and I have 8GB of ram allocated to tekkit legends. Im running windows 10 64bit and i have the latest version of 64bit java and no other installations of it. I installed optifine hd ultra 1.7.10 myself. My issue is that everything is laggy. Again, not framerate laggy but when i right click any interactable object it most of the time takes a few seconds to open. Like if i right click a chest it can take upwards of 6 seconds to open the chests inventory screen. I can still run around and do everything as normal, and the chest opening sound lags even more and usually doesnt play until after i've been in the screen for awhile. Also sometimes all the items in my pipes that are going to various crafting tables just vanish and reappear sometime later almost playing catch up going really fast. Energy condensers will show in the screen that they arnt gaining EMC and then gain a massive amount of emc seconds later. Stuff like that. It feels like server latency but i'm playing single player. I don't understand because for years i've seen people with massive worlds and lots of crazy technical contraptions and factories running pcs not as good as mine and them running the game just fine. I've barely started doing anything factory related that I want to do and I'm worried that if i keep playing and building stuff it will get worse. It already feels basically unplayable. Used memory stays between 10-20% it climbs from 1GB up to 2GB, sometimes less, and falls back down to 1GB again.