UPDATE: For those who seeking for Seasonic X-Series PSU, note that the new batch of X-650, X-750 etcc will have new features compare to the previous version (X-660, X-760 etc).

-New modular cables (IINM like corsair AX series, no more braided sleeve one)
-Hybrid configuration switch, the switch is at the PSU itself in which you can set your PSU configuration either in hybrid mode or normal mode.