8GB Kit 2 x 4GB Memory for Dell PowerEdge R300 Server PC2-5300R ECC Registered DDR2-667MHz 240 pin 1.8v DIMM (PARTS-QUICK BRAND). Equivalent to A2257191, A2257192 Speed: PC2-5300R 667MHz Form Factor: 184 pin ECC Registered DIMM 2RX4 Capacity: 8GB Total 2 X 4GB KIT Warranty: Lifetime FOR LISTED SERVERS ONLY. PLEASE DO NOT BUY FOR DESKTOPS.