I bought the store to upgrade my NAS (Synology DS712 +). After installation the system went not even high. Officially, clocked at 1333Mhz memory should automatically adjust to 1066 downward. Only in the aftermath I have read in the Synology forum that this module does not meet specifications for backward compatibility. I get so the older models, the "Kingston ValueRAM PC3-10600 RAM 4 GB DDR3 RAM kit", which apparently should fit, Forum members was lt. Multiple installed successfully.