As a help for others, Lenovo ThinkPad L540 photos and information.
Be aware :
The original LCD cable attach in the back of the LCD and has FRU number 04X4891, it supports both HD and FHD with this type of connector.
In order to use an LCD with the bottom connector, a different LCD cable is needed : FRU 04X4890 for both HD and FHD, and it will involve removing the Keyboard and the top panel of the L540, to change the LCD cable.
Also there are 2 significant versions of the L540, one with Slim LCD and top Slim top cover. And one with Thick top cover.
The Thick top cover version can use Slim LCDs, though some adjustments and lngenuity will be needed as the Slim LCDs often don't align with the screw holes. But it can be done with some "Macgyver" methods.
The Slim top cover will not hold a Thick LCD very well, its not impossible, but will not look good.
Both versions use 30pin EDP LCD cable, be aware of this when looking for LCDs.
The LCDs in the Photos are a mix of Thick and Slim, look up the part number yourself. But mostly Slim have bottom connector.
All the LCDs are prone to develop horizontal lines after approximately 10 - 15 years of use, only IPS LCDs don't suffer from this problem, but can get pixel errors and white spots.
IPS LCDs look a lot better than the normal LCDs and tend to last longer.
OLED and AMOLED suffer from burn-in ghost images, and therefore should be avoided.
BOE LCDs are very cheap and look great, but suffer from Ghost images after a few years.
Better brands are Samsung, LG, LG-Philips, AUO.
Less good brands are CMI.
I have replaced my LCD 2 times, both with original AUO B156xtn02.6 HD only. Because at the time I could not get the Slim LCD cable.
And I were incorrectly informed by Lenovo and some dealers that FHD Slim IPS LCDs would not physically fit.
My next LCD(the first AUO B156xtn02.6 LCD lasted 1 year, the second is still working but it is unknown when(not IF) it will fail), is going to be FHD 400nits(or higher) IPS.
Basically in theory, all LCDs that fit physically and are 30pin EDP, should work. Remember I said in theory, so make sure supplier confirms this.
