An all around great buying experience. I would consider myself an advanced computer hardware and software user, but the chips are relatively easy to install. I opened the Memory compartment of my daughter's Sony Viao and removed the single chip that was already installed. I installed the two new 1GB RAM chips into the top and bottom slots (be careful here; the bottoms or 'pin sides' of the chips go in first, and at an angle, then they can be pushed down until they are lying flat) DO NOT FORCE THEM! If they aren't going in relatively easily, take them out and try again. Be careful with the tiny screws that hold the RAM Compartments shut. I dropped one inside the laptop and it took minutes of careful shaking to retrieve it.
Once the RAM modules are installed, power-on the laptop and (if the chips were installed properly, it should boot through to the operating system without fault) in Windows, go to the Control Panel, then to System and it should display the amount of RAM present on the Computer. If it says 2048 (or close to this number) you have installed the 2Gb chips successfully! If the number reads 1024 (or similar) Gigs of RAM, then one of the chips are not seated properly. Power-down the laptop, open the RAM compartment again and reseat the chips. If one is noticably looser or not seated, just reseating this one should do it. Pwr on the machine again, and again check the RAM amount displayed in the Window's System Properties.