i5 is LGA 1156
i7 is LGA 1366

EDIT:

should mention there is a difference when using multi GPU

here is some more info

 

My local retailer lists the i7 as available in 1366 and 1156....

 

yes, they have a new i7 lynnfield, if you read about what a I7 is according to intel, it is any of their new nehalem based quad core cpu's that have hyper threading.

the i5's do not have hyperthreading.

if you want one with HT, but don't want to pay the price for i7 860, do what i did and get a xeon x3440

 

Quote:

Originally Posted by Mebby My local retailer lists the i7 as available in 1366 and 1156....

This is because the i7 800 series are designed to fit on the 1156 socket. The original i7 900 series (ex i7 920) is designed to fit on the lga 1366 socket.

 

There are both i5 and i7 chips in the lga 1556 socket. The only main difference is that the i7 lga 1366 uses triple channel ram and has hyperthreading to enable 8 threads with 4 cores.

 

the new ones like 860 or 870 are 1156 i believe.

 

Quote:

Originally Posted by transhour yes, they have a new i7 lynnfield, if you read about what a I7 is according to intel, it is any of their new nehalem based quad core cpu's that have hyper threading. the i5's do not have hyperthreading. if you want one with HT, but don't want to pay the price for i7 860, do what i did and get a xeon x3440

I see, I'm not looking to upgrade at the moment was just curious. =] Thanks for the answer.

 

Everything you want to know about the socket's is right here.

http://www.xbitlabs.com/articles/cpu...re-i7-870.html

 

The major differences between Core i7 1156 and the 1366 is that the 1366 has support for DDR3 Triple Channel RAM, x16/x16 SLI/Crossfire modes. While the Socket 1156 Core i7 has support for DDR3 Dual Channel and x8/x8 SLI/Crossfire modes.