I came home from work the other day to find my Late 2011 MBP stuck on full white screen. Had to hold to power button to kill it, and then it would not reboot properly. Up to this point it continues to do the same thing: Apple Logo appears and load begins... once load bar gets to about 2/3 of the way loaded, a distortion or glitch appears across the top half of the screen for a quick moment (less than half a second) before the it goes back to being stuck on white screen. The screen glitch looks sort of like a gray bar spanning across the entire screen... maybe 2/3 of the way up the screen. Other important notes: -My first instinct was to boot from a target disk, since I perform a weekly backup via SuperDuper. This FAILED. The machine would boot into Target mode, but after selecting the backup drive it would simply have the same problem as stated above: glitch, then white screen. -I tested the backup on another machine (MBA) and it worked fine. -I tried removing one of the two RAM sticks. Same problem. Removed the 2nd RAM stick and replaced the other one. Still failed. -Attempted to boot in Diagnostic/Hardware test mode... this failed. -Attempted to boot in Hardware Test mode via network (Option + D). This worked. I ran multiple extended tests. Most of them were coming up clean, but one time it reported a SATA error with the following code: 4hdd/11/40000000:sata(0,0) I then ran the test again, and the SATA error was not reported. Currently attempting more tests to duplicate the code again. -Seeing that code, I began to suspect it was my hard drive. I removed the drive from the MBP, inserted it into an external USB hard drive docking station, and attempted to boot that up on another machine (the same MBA that I used to test the backup). That worked fine, so I suspect the drive (Corsair SSD) is okay. That's pretty much where I've left things thus far. There's only 2 things that come to mind which I have not been able to test: 1) The SATA cable (which would probably require me to buy/replace it) and 2) The secondary hard drive, which is mounted in a bracket in place of the SuperDrive, although I doubt any problem here would cause the machine to behave this way. MBP Specs: Late 2011 MBP 15" Model A1286 8GB RAM 2.4 GHz i7 256 SSD (Corsair Neutron, just under 3 years old) Dual HDD mod (Apple's stock 500GB HDD... probably a Toshiba... mounted in a bracket from iFixit) My main questions are: 1) Is it even worth trying a new SATA cable at this point? I feel like it would at least be able to work in Target Disk mode even if the SATA cable was shot, but I'm not too sure. Might as well save the $40-$50 if someone can rule that out for me. 2) What the hell is wrong with this thing? I'm to the point where I'm fearing for the Logic Board or the GPU. 3) If it is something like the Logic Board or GPU, what kind of response am I going to get at the Apple Store? There's obviously no warranty on this thing since I've swapped out half of its pertinent guts. Even so, I think it's ridiculous to have to pay for a repair on either of those components after 5 measly years, especially after dumping over $2500 into this machine. Thank you for any insight you can lend.