Each item have been tested critically before shipment effected ,We have build several testing stations specially for CPU ,please buy it with worry-free. listings on auction and classifieds sites CM8066201928610 is an OEM/tray microprocessor BX80662G3900 is a boxed processor with fan and heatsink (English version) BXC80662G3900 is a boxed processor with fan and heatsink (Chinese version) 2 x 32 KB 8-way set associative instruction caches 2 x 32 KB 8-way set associative data caches 2 x 256 KB 4-way set associative caches 2 MB 8-way set associative shared cache SSSE3 / Supplemental Streaming SIMD Extensions 3 SSE4 / SSE4.1 + SSE4.2 / Streaming SIMD Extensions 4  ?  AES / Advanced Encryption Standard instructions EM64T / Extended Memory 64 technology / 64  ?  Supported memory: DDR3L-1333, DDR3