I recently bought a Corsair RM550x to replace one that was past its best. It is to go on an old motherboard msi h61m-p31 (g3) and I notice the board has a jpwr2 (AtX 4-Pin ) slot as well as the AtX 24-pin one and the power supply does not come with a similar looking cable. Did I buy the wrong psu or can i still get this to work on this board please? I believe the 4 pin is for the front panel power but could be wrong? I don't want to try and guess here!