2GB Memory RAM Upgrade for the Lenovo Thinkpad R61 Series, T60 Series, T61 Series, X60 Series and X61 Series Laptops (DDR2-667, PC2-5300, SODIMM) at Amazon.com
RAM memory for Lenovo ThinkPad X61
CMS 2GB (1X2GB) DDR2 5300 667MHZ NON ECC SODIMM Memory Ram Upgrade Compatible with Ibm Lenovo® Thinkpad X61 Notebook Ddr2 Pc5300 Sodimm - A38 System Specific Memory - Newegg.com