T420 Upgarde to i5 3470T ?

[WoodyinMN]

Howdy,

I have a Lenovo T420 - currently with the i5 2520M. I have seen some posts on going to a quad core CPU. I want to go to a faster Dual Core. I have a i5 3470T in my M73 Tiny, and it is one of the fastest Dual Core chips I have used. Would the i5 3470T be compatible with my T420? If not, what is the fastest dual core I can run in my T420 without replacing other components?

Thanks in advance,

- btk

[TPFanatic]

That CPU uses a different socket than T420.

The fastest dual core compatible* with T420 is i7 2640m.

*With normal BIOS. With Coreboot BIOS you can put in the 3rd gen processors which are a little faster, the fastest dual of which is the i7 3540m.

I'm running an i5 2520m myself. My general belief is incrementally upgrading CPUs does not yield substantial improvement for a very poor return on investment.

[WoodyinMN]

Thanks TP Fanatic. Different socket is a important point. Also understand the comment about incremental CPU bump. I also have a X230 with i5 3320M. I can tell the difference between that and the 2520M. - btk

[schen]

The best resource that I've used over and over again for many years has been the Wikipedia page of the lists of particular Intel CPUs. If you'll simply do a search for say...... Intel i5, or Intel i7 CPU list, one of the first items Google will return is a page on Wikipedia that has pretty much every i5 or i7 processor ever in order of intro. There will be a section for desktop CPUs and another for mobile ones. You'll be able to cross-reference socket, TDP, L2 cache, etc.; any number of important things.

You'll be able to see that "S" spec (low power), "T" spec (ultra low power) only exist for desktop CPUs as in the mobile world, there's different low power spec coding such as "U", etc.

[WoodyinMN]

NEED HELP - -

I installed a i7 2640m in the T420. It would not boot. I thought at first it may have failed because some cpu paste got on the socket and new cpu. I cleaned them both up and tried again. The T420 would not boot. The power went on - but nothing wrote to the screen. I reinstalled the i5 2520m, and the T420 booted up normally. What gives?

Do I need to update bios for the chip to work? I am running bios version 1.52 right now. I'd appreciate any help on this.

Thanks!

- w

CORRECTION: THE NEW CHIP WAS A I7 3540M. Maybe not compatible?

[RealBlackStuff]

Unfortunately the Ivybridge CPU doesn't work in a Sandybridge motherboard, unless you apply an Ivyrain or Coreboot mod.

[WoodyinMN]

RBS, have done neither. I'm seeing if I can return the 3540m and get a I7 2640m. I messed up.

[axur-delmeria]

I don't think it's even possible to upgrade a T420 to Ivy Bridge without flashing Coreboot.
None of the official BIOSes have Ivy Bridge support, and IIRC it's impossible to add CPU support tables to the BIOS via hacking because Intel locked it all down after the Core 2 generation.