From experimenting and a Voltcraft 3000 power logger
R1 chips do 32~37W at the wall with a 5.6k resitor(12 chips/board) 30~35 gh/s
R1 chips do 27~31W at the wall with a 3.9k resitor(12 chips/board) 29~32 gh/s
R2 chips do 29~31W at the wall with a 3.9k resitor(12 chips/board) 29~30 gh/s
R2 chips do 39~47W at the wall with a 3.9k resitor(16 chips/board) 37~40 gh/s - never kept i going as it will damage the powerbuck
R2 chips do 30~35W at the wall with a 2.7k resitor(16 chips/board) 32~35 gh/s - current setup
Just my 2 cents