Does Macbook Pro have a hardware or software issue? (Constantly Stuck on White Screen) My Macbook Pro Late 2011 (running on Sierra) has suddenly started having the white screen problem and I've tried the following:


NVRAM, PRAM and SMC reset (could not get past loading bar after
entering my user password)
Running in Safe Mode (could not get past loading bar after entering
my user password)
Running in Single-User Mode (fsck shows no problem with the SSD
drive, got white screen after "exit" command)
Running in Verbose Mode (got white screen after I was in verbose mode
or got white screen after "exit" command)
Running in Target Disk Mode (connected with a thunderbolt cable, I
was able to login to my account on the second Macbook by choosing the
main Macbook's SSD from boot selection menu at the
startup on the second Macbook. I copied everything on my main SSD to
an external HDD, so erasing the drive would not be a problem. However, the
second time I've tried this, I could not get past the loading bar after
entering my user password - just like I couldn't on the main Macbook)
Running in Target Disk Mode (this time as an external drive, on the second Macbook I got
the error "macOS could not fix this hard drive, you can still access
files but reformat it asap". So, I thought the SSD on the main Macbook has a problem and
it was causing this problem!)


After this, I've erased the main SSD and tried to install a fresh macOS Sierra into the empty SSD. However, I got a white screen in the middle of the installation! (side note; I was installing from a bootable external HDD via USB).

After many tries and fails, somehow I was able to come to the final stages of installation (where you create a user name, password etc.). I entered the information and hit finish, then the computer just froze (the cursor and everything). I could not finish the installation on the main Macbook.

-Bear with me here-

I was not ready to give up, so I put the main Macbook into Target Disk Mode and I finished the installation on the second Macbook. Logged in, could see my fresh desktop.

I hoped it would work just as fine on the main Macbook, but now I cannot even see the user login screen. The only thing I can see is the Apple logo and the progress bar that never finishes loading (because it gets interrupted with a white screen, it fills 3/4 approximately).

So my question folks, does my Macbook Pro Late 2011 have a hardware or software issue? If it is hardware, what could it be? Keep in mind that I do not have anything plugged in or changed any hardware recently.

Thanks for reading, hoping for an answer.

Cheers &amp; stay safe!

UPDATE: I've installed a fresh macos Sierra to an external HDD and plugged it in my main Macbook Pro, selected that drive using Option key and I still can't get past the loading bar with Apple logo (get white screen).
You've tried replacing all the software and the issue still persists, so it sounds like a hardware issue.

RAM is the easiest hardware to test, so I'd suggest running memtest86+ on your Mac for a while to see if it picks up any problems.