How do I know which Motherboard goes with which cpu.

[Zues]

For example the i5 sandy bridge

 

[janas19]

A CPU fits in a motherboard's socket. In Intel's products they classify the sockets by the "LGA" which is the number of pins/contacts in the CPU. There's LGA 1155, 1156, 2011, 775 - each of these sockets support certain CPUs.
So when looking at Intel motherboards, look at the LGA. That tells you the CPUs it is made for.

 

[Puppies04]

1156 = first gen i3 i5 i7 any "I" chip with 3 digits e.g I5 650 excluding any that start with 9 i.e 9XX also some "pentiums" that I wont go into here.

1366 = enthusiast socket first gen "I" chips 3 digits againm but start with 9XX e.g I7 930

1155 = second gen "I" cpus have 4 digits e.g I5 2500 (note they all start with 2XXX excluding the "pentiums" which I will ignore to keep this post clear

2011 = Second gen enthusiast socket 4 digits (note they all start with 3XXX)

Hope that helps

Edit.

1156 = P45 P55 Q57
1336 = X58
1155 = H61 H67 P67 Z68
2011 = X79

 

[paperwastage]

find your CPU via http://ark.intel.com/

(most of the time it should be there)

find Sockets Supported FCLGA1155

 

[piasabird]

If you go to newegg you can select a second generation SB Sandy Bridge motherboard by socket type 1155. Then when you search for a processor you have to use the same socket type and just do a searcy by socket type. Usually most manufacturers of motherboards will also have a website where they have manuals or technical information about what type of processor works with that motherboard.

Same thing goes for RAM. Most manufacturers of RAM have a website where you can plug in the manufacturer and model number of the motherboard and then they will have their suggested RAM model numbers. I like to be absolutely certain the RAM will work with the motherboard. RAM can be confusing because the motherboard may say it can us up to a certain speed but if you overclock maybe the faster 1600 speed will work. However, some motherboards are very picky about the speed and the voltage rating for the RAM like 14,15,18?