Originally Posted by
Kurzior
General rule for DPS gemming.
Case 1: Red sockets with any stat bonus -> gem pure primary stat (int/agi/str)
Case 2: 1 yellow/blue socket, bonus is +20 primary stat -> gem for the socket bonus, using an int/agi/str + ? gem. The socket bonus makes up for the gem split, giving you a free stat
Case 3: 1 yellow/blue socket, bonus is +10 primary stat -> gem pure primary stat, int/agi/str are usually 2x better than any secondary stat
Case 4: 2 yellow/blue sockets -> gem pure primary stat, unless the bonus is 30 primary stat or better, the bonus will not justify the loss of 40 primary stat