I was amazed when I opened up the back of my Lenovo laptop and tried to install another SODIMM only to find that it was about 0.5mm too wide! I honestly thought that all SODIMM memory was the same. Obviously not! So I ordered this RAM module (which is the exact same as the one on my laptop) and it installed flawlessly. I now have a Gig of RAM which runs Windows 7 happily. A noticeable increase in operating speed too. Good all round memory!