OFFTEK 2GB Replacement Memory RAM Upgrade for IBM-Lenovo ThinkPad X61 (7762-xxx) (DDR2-5300) Laptop Memory at Amazon.com
CMS 8GB (2X4GB) DDR2 6400 800MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with IBM Lenovo® Thinkpad X61 Notebook Ddr2 Pc6400 Sodimm - A41 at Amazon.com
IBM LENOVO X61 take apart video, disassemble, how to open disassembly - YouTube
CMS 8GB (2X4GB) DDR2 6400 800MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with IBM Lenovo® Thinkpad X61 Notebook Ddr2 Pc6400 Sodimm - A41 at Amazon.com
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) - Walmart.com
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
Upgrading the CPU in ThinkPad X61 — Wenting's Web Page
2GB RAM Memory for Lenovo ThinkPad X61 Tablet Black Diamond Memory Module DDR2 SO-DIMM 200pin PC2-5300 667MHz Upgrade System Specific Memory - Newegg.com
4GB 2X2GB RAM Memory for Lenovo ThinkPad X Series X61 (76734NU) Black Diamond Memory Module DDR2 SO-DIMM 200pin PC2-4200 533MHz Upgrade System Specific Memory - Newegg.com