Librem 15 v3 LCD upgrade options and eDP

I was looking at alternative LCD panel options to replace the TN panel that came with my 15 v3 and came across some panels that require eDP 1.2, so I was wondering if the internal eDP interface and cable support it. Theoretically the display interfaces directly with the GPU so it should support it electrically but since the signalling speed is double that of 1.0/1.1 motherboard layout and cable signal integrity may be the limit.
Also is there a firmware limitation somewhere (in coreboot?) as to which panels are supported?

The stock panel (TN, 262k color ,60Hz) is this one: http://www.panelook.com/HB156FH1-401_BOE_15.6_LCM_overview_23016.html

Panels with the same specs (dimensions and interface) but IPS and 16.7M color:
http://www.panelook.com/LTN156HL06-C01_Samsung_15.6_LCM_overview_24666.html
http://www.panelook.com/NV156FHM-N31_BOE_15.6_LCM_overview_25044.html
http://www.panelook.com/NV156FHM-N41_BOE_15.6_LCM_overview_25578.html
120Hz:
http://www.panelook.com/B156HAN04.2_AUO_15.6_LCM_overview_32204.html
http://www.panelook.com/B156HAN04.5_AUO_15.6_LCM_overview_33006.html
144Hz:
http://www.panelook.com/NV156FHM-N4B_BOE_15.6_LCM_overview_34862.html

There are also 262K 60Hz IPS panels (too many to list here) that should use the same interface as the stock one so I’m guessing they should work if the eDP 1.2 ones don’t.

That’s interesting, thanks for that list.

But one thing is not correct in there - all Librem laptops since V3 come with IPS panels. Also V1 and V2 were mostly IPS, except one batch of L15v2 where had to accept TN because of supply chain issues.

Cheers
nicole

2 Likes

I must have a rare specimen then, it’s definitely TN:

hd /sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/edid
00000000  00 ff ff ff ff ff ff 00  09 e5 2b 06 00 00 00 00  |..........+.....|
00000010  01 18 01 04 95 22 13 78  02 b0 90 97 58 54 92 26  |.....".x....XT.&|
00000020  1d 50 54 00 00 00 01 01  01 01 01 01 01 01 01 01  |.PT.............|
00000030  01 01 01 01 01 01 3c 37  80 de 70 38 14 40 30 20  |......<7..p8.@0 |
00000040  36 00 58 c1 10 00 00 1a  00 00 00 00 00 00 00 00  |6.X.............|
00000050  00 00 00 00 00 00 00 00  00 00 00 00 00 fe 00 42  |...............B|
00000060  4f 45 20 48 46 0a 20 20  20 20 20 20 00 00 00 fe  |OE HF.      ....|
00000070  00 48 42 31 35 36 46 48  31 2d 34 30 31 0a 00 e8  |.HB156FH1-401...|
00000080

dmidecode:
System Information
Manufacturer: Purism
Product Name: Librem 15 v3
Version: 3.0
Serial Number: 277794

The bottom cover also says v3. It’s possible the display was already replaced since I’m the 2nd owner and don’t know much about the history of the device.

unlikely, since the bezel trim on these requires significant effort to remove without marring.

FWIW, the 15v3 I have here definitely has an IPS panel:
http://www.panelook.com/NV156FHM-N42_BOE_15.6_LCM_overview_26390.html

Thanks. That’s one of the 262k color panels I was looking at, good to have a confirmation it works.
I’m sure the one I have is stock since the bezel shows no marks of ever being removed. If it was replaced the whole display assembly was replaced in one piece but I doubt it.
I assume the way to get these apart is the same as all new machines with glued on bezels. A challenge but certainly not impossible. I have experience with hot air working on smartphones and surface mount PCBs so I’m probably just going to buy a new panel and replace it myself. If there were a way to get the whole assembly new or used somewhere I’d maybe consider buying the whole thing, depending on the price.
The only thing I wanted to know is if eDP 1.2 16M color panels are compatible, if not I’m just getting one of the 262k color ones.

Oh, I start to see the problem… the Serial Number: 277794 tells it… this is a very early V3 system, at a time where we just switched the version and also the panels. The L15v2 mostly had TN panels due to supply shortages at the panel makers at that time. Then the V3 development came along and for a brief moment we had a few V3 systems with TN panels - sorry you caught one of these. All newer V3 and especially V4 are definitely IPS.

Cheers
nicole