Sandy Bridge recognized as Haswell & C7 state not showing

[sheepdestroyer]

Compiled last git, I am on Lenovo X220 with Sandy Bridge CPU : i7-2620M
cpuid here : http://pastebin.com/3tJPsHTr

i7z guesses Nehalem instead of SandyBridge and, in the ncurse gui C7 state is not shown, only C6 :

[sheepdestroyer@sheepora ~] $ sudo i7z
[sudo] password for sheepdestroyer: 
i7z DEBUG: i7z version: svn-r93-(27-MAY-2013)
i7z DEBUG: Found Intel Processor
i7z DEBUG:    Stepping 7
i7z DEBUG:    Model a
i7z DEBUG:    Family 6
i7z DEBUG:    Processor Type 0
i7z DEBUG:    Extended Model 2
i7z DEBUG: msr = Model Specific Register
i7z DEBUG: msr device files exist /dev/cpu/*/msr
i7z DEBUG: You have write permissions to msr device files

------------------------------
--[core id]--- Other information
-------------------------------------
--[0] Processor number 0
--[0] Socket number/Hyperthreaded Sibling number  0,1
--[0] Core id number 0
--[0] Display core in i7z Tool: Yes

--[1] Processor number 1
--[1] Socket number/Hyperthreaded Sibling number  0,0
--[1] Core id number 0
--[1] Display core in i7z Tool: No

--[2] Processor number 2
--[2] Socket number/Hyperthreaded Sibling number  0,3
--[2] Core id number 1
--[2] Display core in i7z Tool: Yes

--[3] Processor number 3
--[3] Socket number/Hyperthreaded Sibling number  0,2
--[3] Core id number 1
--[3] Display core in i7z Tool: No

Socket-0 [num of cpus 2 physical 2 logical 4] 0,2,
Socket-1 [num of cpus 0 physical 0 logical 0] 
GUI has been Turned ON
i7z DEBUG: Single Socket Detected
i7z DEBUG: In i7z Single_Socket()
i7z DEBUG: guessing Nehalem