Help upgrading Thinkpad T490 panel

humanplayer2, 11 months ago

Uh, I understand the nervousness of buying the right thing! Expensive and fragile :D

I've been recommended panelook.com, which I've used a lot (though I haven't ordered many screens). There you can also check the physical dimensions, both active and overall. For you original screen, there are a number of revisions, and I'd suggest you check that they all have the same dimensions and the same pin connector location, if you can't identify your revision (maybe it's printed on the label? Maybe not). See https://www.panelook.com/modelsearch.php?keyword=N140HCA-EAC.

I can't see the model number of the screen you suggested, so I can't compare. Personally, I then wouldn't order.

Did you do a search for the best replacement screen? I think a community favorite is N140HCG-GQ2. I've ordered one of those myself, and placed it in a T495. I ordered that from AliExpress. I contacted the seller and asked for the exact model, which they verified they would send. Then I ordered. I bought exactly this: https://a.aliexpress.com/_msLEB5q.

such_lettuce7970, 11 months ago (edited 11 months ago)

Yeah as for the original screen, I can't seem to identify the revision.

edid-decode </sys/class/drm/card0-eDP-1/edid
edid-decode (hex):

00 ff ff ff ff ff ff 00 0d ae d4 14 00 00 00 00
24 1a 01 04 a5 1f 11 78 02 28 65 97 59 54 8e 27
1e 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01
01 01 01 01 01 01 b4 3b 80 4a 71 38 34 40 50 3c
68 00 35 ad 10 00 00 18 00 00 00 fe 00 4e 31 34
30 48 43 41 2d 45 41 43 0a 20 00 00 00 fe 00 43
4d 4e 0a 20 20 20 20 20 20 20 20 20 00 00 00 fe
00 4e 31 34 30 48 43 41 2d 45 41 43 0a 20 00 05

----------------

Block 0, Base EDID:
  EDID Structure Version & Revision: 1.4
  Vendor & Product Identification:
    Manufacturer: CMN
    Model: 5332
    Made in: week 36 of 2016
  Basic Display Parameters & Features:
    Digital display
    Bits per primary color channel: 8
    DisplayPort interface
    Maximum image size: 31 cm x 17 cm
    Gamma: 2.20
    Supported color formats: RGB 4:4:4
    First detailed timing includes the native pixel format and preferred refresh rate
  Color Characteristics:
    Red  : 0.5898, 0.3496
    Green: 0.3300, 0.5546
    Blue : 0.1533, 0.1191
    White: 0.3134, 0.3291
  Established Timings I & II: none
  Standard Timings: none
  Detailed Timing Descriptors:
    DTD 1:  1920x1080   60.008 Hz  16:9    67.929 kHz 152.840 MHz (309 mm x 173 mm)
                 Hfront   80 Hsync  60 Hback 190 Hpol N
                 Vfront    6 Vsync   8 Vback  38 Vpol N
    Alphanumeric Data String: 'N140HCA-EAC'
    Alphanumeric Data String: 'CMN'
    Alphanumeric Data String: 'N140HCA-EAC'
`
```

"CMN5332" doesn't appear in any searches on laptopscreen.

What you bought though, do you think that will fit my T90? I also don't know if I need brackets or tape and I've been giving myself a headache trying to figure all this out.

humanplayer2, 11 months ago

Yes, I think so. I the T495 is - as far as I know - just the AMD version of the T490.

I think it's ok that you can't find the revision of your screen. Just check the different revisions on panelook. I suspect they'll match in dimensions and connector position. I Mena, they ought to, as they are the same model number, and the revision apparently is so unimportant that it doesn't get stated by the screen itself.

such_lettuce7970, 11 months ago

I looked up my serial number and I got this: https://pcsupport.lenovo.com/us/en/products/laptops-and-netbooks/thinkpad-t-series-laptops/thinkpad-t490-type-20n2-20n3/20n3/20n3s2ya00/pf14q52k/parts/display/as-built?linkTrack=Caps%3ABody_SearchProduct&searchType=6&keyWordSearch=pf14q52k which lists two displays (so I guess mine could have either) but neither has brackets. So I should pick a new display without brackets too?

humanplayer2, 11 months ago

I'd personally do that. You can clip them off of course, but I don't know how they affect the dimension measurements.