XPS 13 2015 9343 (QHD) with Ubuntu 15.04: screen goes blank at random times

Running 14.04 and also having this problem.

Looking at kern.log, and googling for errors like 

Jun 4 09:35:12 bit kernel: [ 1048.363704] i915 0000:00:02.0: BAR 6: [??? 0x00000000 flags 0x2] has bogus alignment
Jun 4 09:35:12 bit kernel: [ 1048.365176] i915 0000:00:02.0: BAR 6: [??? 0x00000000 flags 0x2] has bogus alignment
Jun 4 09:35:12 bit kernel: [ 1048.365309] i915 0000:00:02.0: BAR 6: [??? 0x00000000 flags 0x2] has bogus alignment
Jun 4 09:35:12 bit kernel: [ 1048.365329] i915 0000:00:02.0: BAR 6: [??? 0x00000000 flags 0x2] has bogus alignment

I found https://bugs.launchpad.net/xserver-xorg-video-intel/+bug/1432194, 

I have the same problem - and suspending makes the screen wake up again. (I close the screen to do that.) Running Ubuntu 14.04 (Linux Mint 17.2). Sometimes it happens several times in short succession. Thanks for posting the Launchpad link! (For anyone getting an error message, there's an extra comma at the end of the URL.)

Recently something related happened, not sure whether I should create a new topic so I'll write it here.

The screen was also dark, but neither did the caps lock light on the keyboard work and closing the screen would not suspend the laptop. At the same time, there was still network activity (I use an external USB ethernet card). No reaction on restarting Xorg with CtrlAltBackspace.The only way to get the screen back was do to a hard reset.

I've been having this issue since around the beginning of August.

When it first occurred in Ubuntu 15.10, I booted to my Win10 partition and experienced the same problem.  Also, I this happened while signing in and even before loading the operating system.

After several occurrences of "blank screen and num-lock inactivity" and corresponding hard-resets, I decided to upgrade Ubuntu from 15.10 to 16.04.  After this, the problem did not manifest again until today.

I upgraded the bios to the latest version A09, or is it A10?

Interestingly, every time I log into dell support and ask it what drivers I need, It tells me that I need to upgrade my bios.  Strange that it is labeled both A09 and A10.

Deductive logic suggests that this is a hardware issue.

One other observation:  a few months ago I received a call from a person claiming to be a representative of Dell.  He informed me that my computer was "pinging" his servers over the last few days from my bios, and that he was required to call me.  After I informed him of the fact that my PC has been offline for nearly 3 weeks, he rudely told me that he had to call me because my computer was calling for help or some nonsense.  I hung up.

I wonder if Dell has had some kind of security breach in their system and malicious bios updates or some kind of fishy business going on.  

It is fairly upsetting that no support for this issue is available, and since my computer is out of warranty, I cannot have the problem fixed.

Could it be possible that dell is purposely wrecking people's machines who do not have warranties, in the hopes that they cough up the ~300 dollars?

Only other option is to replace the motherboard on Ebay for around 200 dollars.  I think this will work because it controls the voltage from the power supply, the video card, RAM, and processor; and that I find it highly unlikely that any of the other components could be causing the issue.  Here is a link explaining how to do this.

The Dell representative I chatted with ignored my question, "have you heard of instances of this 'black screen' problem before?"  Instead, he informed me of the ~300 dollar service plan.

I find it convenient for Dell that this issue began literally 1 month after my free 1 year warranty expired.

So I'm faced with the option of paying ~300 dollars to Dell to fix the problem by sending my computer in and waiting for them to fix it and all that, or fix the problem myself for ~200 dollars, knowing that Dell or some other entity may still be able to mess my stuff up.