/tpg/ Objective Model Guide

For freefags who don't mind a slower PC / need LibreBoot and willing to SPI flash:
T400 - 14", normal size
T500/W500 - 15.6", slightly bigger, 16:10 aspect ratio, up to 1920x1200 FlexView
X200 - 12.5", ultra portable

For normal users who need the classic keyboard / need Coreboot and willing to SPI flash:
T420 - 14", normal size (will support Libreboot by 2018)
T520/W520 - 15.6", slightly bigger, takes a TN 1080p display
X220 - 12.5", ultra portable (will support Libreboot by 2018)

For users who like the new keyboard, or want to swap the classic one in:
T430 - 14", normal size
T530/W530 - 15.6", slightly bigger, takes a TN 1080p display
X230 - 12.5", ultra portable (supports Coreboot)

For users who like the modern style and the new touchpad, or want to swap it out:
T440p - 14", normal size, beautiful FHD IPS display, takes Intel 7260 ac+BT without whitelist. *NO EXPRESS CARD SO NO eGPU!*
T540p/W540 - 15.6" / 15.5", slightly bigger, takes a 15.5" 3K IPS display, takes Intel 7260 ac+BT without whitelist.

W series are generally identical to T series, with the exception of having a different, more CAD/work oriented graphics cards.

xx20/xx30 have notoriously awful screens, and FHD/2K upgrade kits are fucking unicorns, so don't ever count on getting them. Alienware 1600 x 900 TN screens, however, are known to be very nice (almost IPS-like), and run well on them.

The T440/X240 is NOT recommended because it has no real performance gains over the previous generation (only better battery due to ULV) and does not have a slice battery. Both do, however, accept a third party 1080p IPS display. The X240 also only has one RAM slot, which degrades iGPU performance and caps the ram at a single 8GB stick.

xx40 models have a "clickpad" instead of a normal TouchPad. It is notoriously awful, but you can easily swap it out with any of the xx50 model TouchPads, which are normal 3-button ones, and better quality than before.

All xx30 models will not take an AC network card without doing an SPI flash of a modified BIOS.
All pre-xx30 models will not take an AC network card without a software BIOS flash.
All xx40 models take the Intel 7260 ac+BT.

Instructions for SPI flashing are here: https://libreboot.org/docs/install/rpi_setup.html
The pinouts and procedure are the same for all ThinkPads (confirmed and tested), but lookup your chip model for the flashing part (replace -c "MX25L1605" with your model).

All M, QM/MQ, and XM/MX CPU sockets are socketed. All X2** and the T440 are soldered CPUs and not upgradable.

T4**(p) series should NOT upgrade to Extreme Edition CPUs due to massive heat issues, but can take the top of the line QM/MQ chips fine IF you use an integrated GPU AND swap your heatsink out for the dedicated GPU version, which carries an extra copper pipe to help cool better. This is only necessary for 45W/47W CPU upgrades, 35W/37W QM/MQ chips run well without this mod.

T5**(p) series can run Extreme Edition CPUs just fine.

BIOS mods allow you to overclock Quad Core and Extreme CPUs, with the latter being able to go as high as 4.6GHz safely on 15 inch models.