Thanks for the reply. I am using Toshiba Satellite C850-X0100.
You can check the configuration of my laptop in the below link.http://www.toshiba-india.com/laptop/satellite-c850-i5-viewmodel.html
It has i5 - 3210 - 3rd generation.
I am using windows 8 right now. 64Bit. Planning to dual boot with Fedora or SUSE
Will be mostly doing development work so thought it will be good to add 4GB more.
In CPU-z, SPD is showing 2 slots and DRAM Frequency ~ 798 [Not sure if you asked for it.]