Patriot Signature Line DDR3 4GB 1333MHz Single Module PC Memory PSD34G13332H Capacity: 4GB PC3-10600 (1333MHz) dual Data Rate 1.5V Power Requirement; 7.8US Refresh Interval (8192 CYCLES/64MS); 2 Rank Double-sided module Non-ECC Unbuffered; 240-Pin Dual in-line memory module