Lenovo T440 Thinkpad Upgrades

Lenovo Thinkpad T440 with Full HD IPS panel

(The upgraded T440 with a full HD IPS display. Click for a larger image.)

This ThinkPad was given as a scholarship to one of my children who was going off to college. Here are the specifications as it was shipped in late 2014:

This was not a bad machine at the time except for the screen, which just did not have enough resolution. The screen it was shipped with is was a TN (Twisted Nematic) panel which is good for response time but has poor viewing angles and color reproduction.

The first upgrade years ago was to replace the Hitachi hard drive with a 250GB Samsung SSD. That made the machine much more shockproof and also improved the usability substantially.

Over the years the machine was heavily used. A USB socket had to be resoldered and secured and the original screen was replaced after something was dropped on it. When the second screen was broken last fall I decided to replace the entire machine with a new ThinkPad and retire this one. (This is a ThinkPad family.) This particular ThinkPad served honorably.

As it sat around collecting dust the broken screen bothered me. For around $100 I could replace it, but then I would have a 6 year old laptop with a crappy screen. So I started digging around, looking at Reddit posts, YouTube videos, reading all of the comments, etc. Here is what I learned:

What I was missing was the specifics. For example, people would say they had upgraded a T440 but not the specific type or model number. If somebody had said “20B6” I would have been so much happier.

So I kept digging. PCsupport.lenovo.com will let you use your machine’s serial number to look up the original part numbers and compatible part numbers. From there I was able to figure out the 1366x768 and 1600x900 replacement options. However, this confirmed that even with some reports of 1920x1080 working it clearly was not tested or supported by Lenovo. Another wrinkle is the connector cable; all of these displays use embedded DisplayPort (eDP) but eDP cables can be one or two lanes. The lower resolution screens (1600x900 and lower) require just one lane while full HD 1920x1080 requires two lanes. And of course, looking at the cable I had in the machine told me nothing - there was no recognizable part number or FRU number on it.

Eventually I came to the conclusion that it was worth the risk to try it out so I ordered what was supposed to be a compatible screen. I had some starting part numbers from the earlier research I had done. I used panelook.com to check the specifications for the screens that were supposed to work, and then I ordered a compatible screen.

I requested a panel made by AU Optronics (AUO) but I wound up with an LG panel because of a shipping mistake. I tried it out anyway, and it worked! After an hour I started to look at it more critically, noticing a significant cluster of dead pixels and other sub-pixel defects in the screen. So while I was disappointed, I had what I needed - the upgrade was clearly possible.

Fast forward … here is what the machine looks like now:

I say “new” about the batteries because the batteries that were shipped to me were sitting on a shelf for at least two years, which is not a good thing for lithium-ion batteries. The powercfg tool under Windows 10 is reporting 43930 mWh on a full charge for the two batteries, so it is probably OK. There was an option to go with a bigger external battery called the "68+" but I passed on it as it was 2x the cost of the 3 cell battery and it would probably overkill for this machine. (Although I can always upgrade later, and since those probably sell more they will probably be fresher.)

Here are the vendors I used:

Thinkpads are designed to be serviced. On this particular machine you have to remove some screws on the underside of the machine and gently pry the plastic apart. Doing this exposes everything you need access to:

Lenovo Thinkpad T440 internals

(Lenovo Thinkpad T440 internals. Click for a larger image.)

I noted the location of the eDP cable and connector, but that is just for reference - you will not need to touch it except where it interfaces with the display panel. The CPU fan is noted because you might want to blow the dust out of it while you have access to it.

Installing the replacement panel is fairly easy. You have to use some finesse to remove the plastic bezel to expose the panel mounting hardware. After that though, it is just four screws and the eDP connector to deal with. The eDP connector is a small, 30 pin connector at the bottom of the panel - they are not designed to be exercised so be careful and minimize the number of times you manipulate it.

Lenovo Thinkpad T440 display bezel removed

(Lenovo Thinkpad T440 with the display bezel removed. Click for a larger image.)

Miscellaneous notes:

Investing 10 hours of research and close to $350 in a six year old ThinkPad? Probably not too smart. But I learned a lot and I’m using a machine that is literally better than any that left the factor, as the full HD IPS display was never an option. And I'll get a few more years of use out of the machine, preventing it from becoming e-waste for a while.

Created March 21st, 2021
(C)opyright Michael B. Brutman, mbbrutman at gmail.com