A laptop display, works normal in use. When set to power off screen after some minutes of inactivity, vertical stripes show up and disappear quickly (<200ms) after the screen is woken up.
This is when screen is off for at least a minute (sometimes more or less, but difference is not large).
If he's awaken 10 seconds after entered sleep, there are no stripes.
I left it sleep for 5 minutes and heated with 100 celsius - there were no stripes when waking up.

What to change?

Another cable tried, no difference

did you warm the whole laptop in the case?
replace the display to check
check the power supply voltage at the moment of awakening
wrap in dough
make a pie

warming up only lcd board
i have LG display that is also faulty. that one showing horizontals stripes, but not only when waking up, also when shutting down entire machine
both displays tested on 3 boards and always the same. the boards were taken from ebay in germany, aliexpress in china and one i bought locally - this one came with entire laptop it had the issue before i took it apart

i soldered brand new northbridge (which integrates gfx processor) taken from supplier in poland, it starts every time there is no problem about it.

still have lcd board from my original broken samsung screen that worked perfectly. some components are identical on these two boards

what device are you repairing ???

HP 6735B
Mainboard is repaired, works fine.
Only thing left to repair is the screen. It is not critical, but since this is my laptop and I'll be using it I need to get rid of this annoyance.

a short circuit found on 3 capacitors marked in photo
clear short 0ohm
there is 2.5V on them when powered on

is this a problem?

3.38V on the cable with screen detached
3.23V with screen

too low?

402WP checked it is not damaged

2x N10, KJH, K77, 402WP replaced, no change

B1, B2, B3 are inductors so no short there

There are i7512, i7822, i7975, one more KJH, 2x K1N, MJ8A, RT9193, 2x memory chips and main wiseview chip that i didn't replace. Also 3x very small chips i couldn't even identify they marked KJGW4.

Somewhere i read those ixxxx chips are to reduce flickering. When entire machine wakes from suspend there is very noticeable flickering on the bottom of screen (but not every time)

To get 7975?

It was broken in corners and not worth the repair anymore. Close