Display woes: LCD died, 4k monitor flickering

My Alienware 18 shut off this morning, and then took a couple tries to boot up again, however the display failed to ever power on. I spent hours taking everything apart, resetting BIOS, etc because it didn't work on the first external monitor I used, so I assumed it to be something a little more sinister. Eventually I exhausted all other options and so decided to try a new 4k monitor, which, to my relief, shows that it is in fact only a display issue and that everything else is still working fine. I can use it on the monitor at 1080p.

It works properly up to 1920x1440, however at 2048x1536 and above, it becomes unusable. The display is very intermittent, with my desktop only visible as it 'flashes' into sight for a very brief moment every couple of seconds. Obviously this defeats the purpose of having a 4k monitor at all. I have tried several HDMI cables, including the one that came with the 4k monitor, and I can't set DisplayPort to anything above 1920x1080.

I have run the LCD BIST but I still get no response from the mobile display. It's not even black, I can't see a backlight at all, it's completely dead. In the course of initially trying to fix it, I would have adjusted the connections at least 2 or 3 times and yet the problem persisted.

If it's significant, when it died I was using the HDMI In and DisplayPort Out (don't judge me but I really like the AW18 screen for playing PS4, and so I use DP at the same time to still be able to use my PC). I have done this for hundreds of hours over the last few months and never had any issues. Today, however, soon after I started playing, the laptop abruptly switched off.

So....
1. Is there any way to know for sure what is faulty? Motherboard on the way out? Cable issue? Or is the LCD actually fried? (I have an old Alienware M17xR3 here; I have no idea if it would be possible to pull that apart and plug the display in for the sake of testing?)
2. Is it likely that the HDMI cables are preventing me outputting 4k? I'll try a new one rated for 4k tomorrow.
3. Shouldn't I be able to set 4k using the DisplayPort?
4. Why me?

 

This article explains the resolution limitations for HDMI and DP. HDMI vs. DisplayPort vs. DVI vs. VGA: Which connection to choose? - CNET

Yes, it should work on DP. It should also work on HDMI.

Do you have an "ordinary" monitor you can try? It sounds like the LCD may have gone belly up. Did you check inside of the display assembly to verify the LVDS cable didn't somehow come loose on the LCD end? I remember a couple of folks posting that this happened on an M18x once upon a time.

 

Thanks, Mr Fox, not sure what I'd do without your tech support on here.

I opened up the LCD and couldn't see anything obviously wrong.

I tried plugging the M17xR3 LCD into the motherboard, and whilst the connection is the same, it's no surprise that I got the 8 beeps indicating that the LCD is incompatible.

Interestingly, I plugged the 18's LCD into the 17 and got a response, albeit a weird one. It flashed white for a couple seconds, then went to an unhealthy grey. This also gave the beep code for a bad LCD, but at least it did something that suggests it's not entirely dead and unresponsive.

Unfortunately I don't have access to another 18 to confirm if it's the LCD or the mobo, but this points to the latter in my opinion.

Fun fact: Don't connect an incompatible LCD to a motherboard or you'll see some smoke (amateur hour here )

This 18 has been nothing but headaches for me from day one, so I'm now wondering if it would be possible to put the 4940MX and one of the 880Ms into my M17xR3 and ditching the 18 husk (answer seems to be yes from what I've Googled, with a bit of fiddling with drivers) . I'm tired of it and I miss the 17.

 

Never mind the last point, of course they have different sockets so that was a silly thought.

I wonder then if it would be possible to disable the LCD check so I can just leave it off and assemble without it. Considering that I use it at my desk 99% of the time, this would be a decent solution until I decide to buy a new LCD or a new motherboard or a new CPU for the 17 and go back to that.

 

You would need an unlocked BIOS to change the default output from LVDS to external display. Unfortunately, it's not looking like Alienware intends to help us with the 18... to the contrary, they have blocked us. It's unfortunate... the machine had potential to be great.

Maybe you can find an inexpensive Clevo with SLI and Haswell chipset with low specs that you can transfer your CPU and GPUs into. You may be able to recover some of the cost by parting out the 18 on eBay. You can get two to three times more for the used parts than they cost buying them brand new from Dell.

 

Fortunately the cable is just long enough that I can leave the hinges detached and 'bend' the screen under the base. With this tension though, a big bump would probably almost snap the connection off the motherboard, so this is far from ideal (god how I would love that mythical unlocked BIOS you refer to).

At this point I'm thinking I'll buy a new CPU for the 17" and go back to that. I've never felt entirely comfortable using the 18 (like that feeling you get when you use someone else's setup, and your fingers never quite seem to be in the right spots and nothing ever feels quite 100% intuitive).

 

I thought I should update this thread for anyone with a similar problem. Buying a new HDMI cable rated for 4k did fix the problem. The 4k monitor worked fine as soon as I used that.

Still no solution for the dead LCD though, so the AW18 is in a million pieces and never to be used again.