# How to set NCORE, KPAR and NBANDS to speed up calculations on VASP?

I am searching of how to set the tags NCORE, KPAR and NBANDS on a specific systems to speed up calculations. Could you please tell me the rules to follow ?

Hence its bit tricky to answer fully that how much resource I need for optimum result. one can easily benchmark their cluster/machine by simple scf calculation. or just follow https://github.com/JMSkelton/VASP-GPU-Benchmarking. Let me discuss what is commonly observed results, KPAR= number of nodes, AlGO=Fast (RMM-DIS also fails in many complex system) NCORE= determines how many cores work on one orbital (Try 4,8, up to number of core per node to find optimal) Generally NCORE=8 or 16 is enough. NPLANE,NSIM,NBANDS are three other parameter you can play in your system but keep checking on amount of memory calculation is demanding. There are several studies has been done on this