AMD Phenom II X6 Black 1090T

Model: 1090T Thuban
Operating Mode: 32 bit/64 Bit
Socket: AM3
Core Speed: 3.20 Ghz
System Bus Speed: 4.0Ghz
Cache: 6 MB
# of Cores: 6

i7 - 2600k

The 2600k is going to be back in action as it was underground due to the Mobo issue. Most probably it will stay unbeaten till 4 to 5 months in price and overclocking.
We do say go for i5 - 2500k as it is 100 $ cheaper than the 2600k
and 
overclocks very well.
So good luck for your Sandy bridge builds.

i7- 2600K

Specifications:        
Sandy Bridge                         

Processor Number: i7- 2600K

Launch Date: Q1 2011

Number of Cores: 4

Number of Threads: 8

Clock Speed: 3.40 GHz

Turbo Boosts upto: 3.80 Ghz

Cache : 8.0 MB

Instruction Set:: 64 bit

Lithography: 32 nm

Bus Type: DMI

It supports upto 32 GB of memory of 1066/1333 DDR3 types, it is dual channel. Max Bandwidth is 21.

It needs LGA 1155 chipset for the motherboard.

It has a price of  $329.99

i7 - 2600S

Specifications:        
Sandy Bridge                         

Processor Number: i7- 2600S

Launch Date: Q1 2011

Number of Cores: 4

Number of Threads: 8

Clock Speed: 2.80 GHz

Turbo Boosts upto: 3.80 Ghz

Cache : 8.0 MB

Instruction Set:: 64 bit

Lithography: 32 nm

Bus Type: DMI

It supports upto 32 GB of memory of 1066/1333 DDR3 types, it is dual channel. Max Bandwidth is 21.

It needs LGA 1155 chipset for the motherboard.

It has a price of  $306

Intel i7 Processors

i7 - 2600S
i7 - 2600K