DDR3 transfers data at eight times the internal clock rate. JEDEC specs lowered DDR3 voltages down to a typical 1.5V and provided for chips of up to 8 GB. Official DDR3 standards run from DDR3-800 (PC3-6400, CL5 or CL6) up to DDR3-2133 (PC3-17000, CL11 to CL14). As with prior DDR formats, DDR3 SODIMMs can optionally include error correcting code (ECC) or be “registered” for improved signaling, both features common in business systems.
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