UHD panel upgrade T14/T15 gen 2: odd behaviour
Posted: Mon Dec 06, 2021 1:32 pm
Hi all. I'm trying to do some problem solving... I bought my father a 15.6" UHD panel upgrade (AUO B156ZAN04.1) to replace the original FHD panel in his T15 gen 2. I bought a compatible 40-pin eDP UHD cable (narrow 0.4mm pitch) and connected the panel and board
photos: https://imgur.com/a/Ln1YZGY
On boot, the Lenovo logo displays correctly, and BIOS also displays correctly. When booting into ubuntu, the picture displays correctly at 3840x2160
However... in Windows 10, there are vertical stripes across the whole screen and it appears black and white. It seems almost as if the RGB channels are out of horizontal synch, as they seem offset from each other. It seems like an hsynch issue - which I've never come across on a digital video signal, but was not uncommon with analog VGA
Laptop is on the Newest Windows 10 update, newest BIOS, newest Intel graphics driver, newest ThinkPad Monitor file, and newest NVidia T500 graphics driver...
I've tried disabling the Xe graphics driver - without change. Same with disabling the NVidia driver.
any ideas? It seems almost certain to be a driver issue... I just can't figure out which one
I've also tried a 40 pin eDP 0.5mm pitch cable with a QHD 2560x1440 panel, and UHD 3840x2160 panel and it works perfectly...
photos: https://imgur.com/a/Ln1YZGY
On boot, the Lenovo logo displays correctly, and BIOS also displays correctly. When booting into ubuntu, the picture displays correctly at 3840x2160
However... in Windows 10, there are vertical stripes across the whole screen and it appears black and white. It seems almost as if the RGB channels are out of horizontal synch, as they seem offset from each other. It seems like an hsynch issue - which I've never come across on a digital video signal, but was not uncommon with analog VGA
Laptop is on the Newest Windows 10 update, newest BIOS, newest Intel graphics driver, newest ThinkPad Monitor file, and newest NVidia T500 graphics driver...
I've tried disabling the Xe graphics driver - without change. Same with disabling the NVidia driver.
any ideas? It seems almost certain to be a driver issue... I just can't figure out which one
I've also tried a 40 pin eDP 0.5mm pitch cable with a QHD 2560x1440 panel, and UHD 3840x2160 panel and it works perfectly...