X121e itch to change i3 to i7

[lambcutlet]

hello,
 i have an old laptop a Lenovo X121e 3045cto. i'm thinking of swapping the processor form an i3-2367m to an i7-2617m

now the X121e was never supplied with an i7 the i3 processor was the highest spec. (motherboard part no. 04W3372)
i have searched the intel datasheets and i have found several i7's i think are swappable all have the same footprint FCBGA1023 and same power rating 17w.
the alternates i think are
i7-2617m (available from ebay at a reasonable price, the one i intend to use)
i7-2637m
i7-2657m
i7-2677m

I have the means to swap the chips, but i am unsure about the bios.
looking through the forums, micro-code seems to be a common modification.


Would the default bios work?
or could one of you kind people assist?

Do you think it would work?

the latest bios is here: 3045cto bios

[DeathBringer]

Post screenshots of first (CPU) & third (Mainboard) tabs of CPU-Z with native CPU.

[lambcutlet]

Post screenshots of first (CPU) & third (Mainboard) tabs of CPU-Z with native CPU.

here are the images:
   
   

[DeathBringer]

This CPU is soldered. Replacement will be too expensive.
But you are right - all i7-26x7M are suitable.

[lambcutlet]

This CPU is soldered. Replacement will be too expensive.
But you are right - all i7-26x7M are suitable.

Thanks for confirming they are suitable. 
the i7 i can get for 25quid, a sacrificial motherboard i can get for 30. this is why it is an itch. For not much outlay i could potentially double the cpu performance + improve the graphics, with just a little effort. And if it fails all i have lost is some pennies. The original motherboard will be untouched.