HYS72T512922ER-3.7-B 4GB PC2-4200 DDR2-533 2Rx4 240-pin Registered ECC SDRAM DIMM HYS72T512922ER-3.7-B 4GB PC2-4200 DDR2-533 2Rx4 240-pin Registered ECC SDRAM DIMM Equivalent OEM part number: HYS72T512022HR-3.7-A, KVR533D2D4R4/4G, HYS72T512922ER-3.7-B, HYS72T512022ER-3.7-B, M393T5166AZ3-CD5, 41Y2722.