Laptop display problems ASUS TUF A15

[mitaux8030]

Daughters' laptop, an ASUS TUF A15 has display problems, mostly the victim of 'fiddling'

The issue started out as a white flickering line at the top of the display. After some research, this is apparently a fairly common problem with the A15, and the solution is apparently to change the display refresh rate. That done, the display was good.
But, continued fiddling in an effort to 'make the display work better' resulted in no display at all on the laptop, and could only get a display on an external monitor via the HDMI porrt.
So, dad to the rescue again - found there were two display drivers installed. Proceeded to uninstall and delete both, which went fine. Windows 10 then used it's default driver, which restored the laptops' own display. Windows then proceeded to replace it's default display driver with whatever it thought was the correct display driver... screen flashed momentarily and then came good again. Looking promising!
But then I decided to see if the fix would survive a restart. It didn't. No display at all again - this time even with the external monitor (and yes, the appropriate Fn-F key is pressed to switch to external display - external monitor reports 'no signal')

It was then that I noticed that ASUS boot up banner / POST / BIOS options were not being displayed on restart or cold boot - just a thin strip of display at the top.

SO, my guess is that the laptop display panel has indeed hardware failed, and that it was only working at a certain refresh rate which was set under Windows, but now that the driver has been replaced, it's trying to display at a refresh rate the panel isn't working with. Likewise, the POST screens also try to display at a refresh rate the panel no longer works with. Would that be a correct assessment of the situation and screen panel replacement is required? Or is there something else that can be tried first, bearing in mind there's no display at all - even with an external monitor - making it impossible to manipulate any settings.

[wotnot]

Did it used to POST to externally connected display?

[mitaux8030]

I didn't take notice unfortunately

[wotnot]

M'kay.... (some of them don't)....is display backlight coming on?

[lsemmens]

Try booting from a Live Operating system, e.g. Linux or Windows installation media. See if either of those show any promise.

[wotnot]

Try booting from a Live Operating system, e.g. Linux or Windows installation media. See if either of those show any promise.

Read again - machine is not displaying BIOS/POST ; this fault is before the OS loads =)

[mitaux8030]

Yep, the display panel backlight is on when booting.
The booting from another media might not be a bad idea, especially if the bootable OS places the display driver in a state where it can handle whatever refresh rate / resolution the display is (was?) happy with. I'll give it a go... of course, that depends on whether the BIOS is set up to look at boot from USB prior to boot from HDD.
Another thing that occurred to me is that daughter likes to pick up the laptop by the open display screen... stressing the display hinges... possibly stressing the display panel connecting cable. Perhaps the cable connection to the motherboard needs a reseat?
But otherwise, a new display panel is a smidge over $200 and doesn't look too hard to replace

[lsemmens]

Check out the govt auction sites, often you can pick up a good specced laptop for a fraction of the cost. And, Yes, wotnot, I was aware of the no-BIOS issue, surprisingly enough, I have had, just that issue on a desktop computer that was displaying nothing until I changed a video driver for the OS. Which is why I suggested a live OS because it worked fine with the live OS and , once the problem was resolved, BIOS display was fixed. Remember UEFI BIOS is different to the legacy BIOS.

[wotnot]

Yep, the display panel backlight is on when booting.
The booting from another media might not be a bad idea, especially if the bootable OS places the display driver in a state where it can handle whatever refresh rate / resolution the display is (was?) happy with. I'll give it a go... of course, that depends on whether the BIOS is set up to look at boot from USB prior to boot from HDD.
Another thing that occurred to me is that daughter likes to pick up the laptop by the open display screen... stressing the display hinges... possibly stressing the display panel connecting cable. Perhaps the cable connection to the motherboard needs a reseat?
But otherwise, a new display panel is a smidge over $200 and doesn't look too hard to replace

What model board? (I've had a look at a few online) ...looks like the backlight circuit is onboard, hence my curiosity ~ if you'd said no backlight, I would've immediately suspected display connector.
That said..given your description of how it's been handled, definitely open it up and check connector ; if that's good, you have to check display cable (continuity checks, usually requires some display disassembly to check that end).
I doubt display refresh rate/resolution has any bearing here (apart from electrical load) --- if it can't display BIOS/POST, this is a board level fault most likely....but it could be display itself, that's why the above check.

Here's a question -- does the unit see time in usage sitting on a bed/pillow or similar (even carpet)....if so, it's probably been cooked =)

[mitaux8030]

Here's a question -- does the unit see time in usage sitting on a bed/pillow or similar (even carpet)....if so, it's probably been cooked =)

Oh yes, typical teenage use, on the bed, gaming for hours on end.

Interestingly, was about to try a Win10 install USB - and the BIOS / POST screen displays fine. Boots - sorta - into Windows, getting the user desktop picture displayed with a little initial flickering at the top quarter of the screen for about 5 seconds but that cleared up. Not fully booting into Windows quite yet, HDD activity ongoing, mouse unresponsive, no desktop icons or menu bar. Going to leave it for an hour to see what happens...
Weird.

[wotnot]

Again, which model is this? These have dual graphics yes?...(stock GPU with a nvidia or such GPU as well?)

Position of display/lid has no effect on the problem?

Anecdotally....okay?....if you pull the harddrive out of a laptop and turn it on (so no OS load, no OS video drivers)...the BIOS/POST screen displays a message similar to 'boot device not found'....yes? No drivers involved...if BIOS/POST doesn't reliably display, it's a hardware fault.

Without actually model number, I can't fill in the blanks =)

[mitaux8030]

ASUS TUF A15 / FA506QM / YMAL 19 94V-0 E114139 / NJF DA0NJFMBAD0 revision D / panel LM156LF2F 03.
Dual graphics - not sure. I suppose they could be configured for on board a la Raedeon, but this one uses a RTX 3060.

After seeing the display return, but no responsiveness (mouse, keyboard etc) after an hour, fiddling daughter couldn't help herself and fiddled more - now back to no display. It's like trying to hit an erratically moving target.

Anyway, after trying the USB boot (no joy) and reseating the display panel cable at both ends (no joy), I very gently flexed the display and was able to get the display to sort of show in parts, but just lines in others. Cleaned off the multitude of fingerprints, food & drink splashes and goodness knows what other crud, there was a tell-tale dark smudge on the panel with the laptop off. I'd say it's suffered a fairly heavy blow or other kinetic event, and the display intermittently working a direct result of that (plus operator induced software repair attempts)

When the display was temporarily working, I was able to observe normal power up behavior and witness the BIOS/POST displays. When display isn't working, those are definitely not displaying. So, 100% display panel fault. Intermittent display might be coincident to temperature; the display appeared to work or mostly work when the room was warm, but that's only an educated guess with limited testing.

Said user now has a relatively (for their budget) expensive-ish replacement panel purchase in their near future, and perhaps learnt a lesson in how not to handle delicate computer equipment will have been learnt?

[wotnot]

Right.....so a radeon graphics core in the CPU and a nvidia rtx gpu ..... so it's -supposed- to have 2 graphics drivers.

Seems like a dead panel ...but then having worked on these dual graphics boards before, they used to bootup on the internal CPU graphics and then switch over to the nvidia GPU (caused consternation in linux years back =)

Unlike your circumstance, I'd have a replacement/spare display to plugin and test first, before committing to the part...ie; I've seen it where the machine boots, picture is fine, but when it switches GPU stupid shit happens (like bad flicker)

Seeing as though I can find an aliexpress store that just specializes in A15 2ndhand mainboards (all models, all ram sizes), that tends to point towards display/keyboard being flaky with this model.

there was a tell-tale dark smudge on the panel with the laptop off. I'd say it's suffered a fairly heavy blow or other kinetic event

Funny....a couple I've seen like this, you could make out the knuckle imprints B^)

[mitaux8030]

Closing the loop on this one: new display panel arrived today, installed and everything is perfect - BIOS/POST screen, Windows, games - all good.
Thanks everyone for your guidance.