Savage HyperX RAM 8 GB DDR3 1600 MHz Non-ECC DIMM Kit Cl9 (2X4Go) XMP, Red HX316C9SRK2 / 8X (Personal Computers)
Works pafaitement recognized by my P55A-UD4 and CM do not clamp my i5-750 to 4GHz. However, it is necessary to indicate the frequency in the BIOS by default to 1333Mhz.