You will need
  • Screwdriver, Everest or cpu-z
  • instructions for motherboard and CPU
The easiest way to know the value of the socket is to take the manual to the motherboard. Locate and open the page which describes its characteristics and view the desired numbers. There's also usually specify a range of processors that will fit to your motherboard. If it is not, then consider the following options.
Knowing the name and manufacturer of your motherboard (this can be read on it, removing the side cover of the system unit) go to the official website of the manufacturer and stating the name of the Board, view its characteristics.
It so happens that many manufacturers often specify a socket in place of mounting the processor on a metal or plastic part of the motherboard. You need to not be lazy, take a screwdriver, Unscrew the bolts of the side cover, remove it, Unscrew the screws holding the fan and radiator cooling the CPU, while not touching the processor, and you in a secret place.
If all the above does not help, then there are programs which scan the system and give your specification. For example, Everest or cpu-z. The more simple it cpu-z. Here we will analyze. Search the Internet or buy in store, install it on the computer. After it starts and wait in the window that appears, locate the graph Package. Here will be listed your socket.
Depending on what CPU you have installed, you can also define what kind of socket you have on the motherboard. This will help you to this list.
Manufacturer Intel

Socket CPU

Socket 370 Pentium III

Socket 423 Pentium, celeron 4

Socket 478 Pentium 4 celeron

LGA 775 Pentium D, Celeron D, Pentium EE, Core 2 Duo, Core 2 Extreme, Celeron,

Xeon 3000 series, Core 2 Quad
LGA 1156 Core i7,Core i5,Core i3

LGA 1366 Core i7
Manufacturer AMD

Socket CPU

Socket A (Socket 462) Athlon, Athlon XP, Sempron, Duron

Socket 563 Athlon XP-M

Socket 754 Athlon 64

Socket 939 Athlon 64 and Athlon 64 FX