Here's how to change or upgrade RAM.
Make sure you know what type of RAM you PC is using.
Here's a reference of RAM type
http://en.wikipedia.org/wiki/DDR_SDRAM
If you don't know what RAM your PC have, it's a good idea to take out the existing RAM and take a picture and show it to the shop.
Make sure shut down the PC and turn off power supply and unplug the power plug before doing any repair or upgrade operations. Stay safe.
