Game in editor keeps lagging

So I have two machines -

first PC - Processor : AMD fx 8370, GPU : GTX 1050 ti 2GB, RAM : 8 GB

Second PC - Processor : AMD RYZEN 1600, GPU : GTX 1050 ti 4GB, RAM : 16 GB

By “maximum size” I mean the maximum component size of landscape that UE4 offers + Fill world button