Hello apple peeps! Really hoping someone here can help me out. So I've been having this weird problem that, for the life of me, I can't figure out. Even after sending it off to Apple Care. Anyway, what's been happening is anytime I start doing something of graphical (or hardware) intensity at some point all forms of input controls lock up. The external keyboard and mouse stop responding, as well as the laptops keyboard and trackpad. Nothing responds until I do a forced shut down, then on restart everything works again until the next "freeze." Odd thing is, everything else continues to function, whether it is a video or a game, video and sound will play like normal indefinitely I just can't do anything. However if I close the laptop and open it back up, the screen goes black and stays black. To further complicate things, this "freeze" is literally THE MOST inconstant system failure I've ever encountered. It happens most often while playing World of Warcraft, but also while using Photoshop, InDesign, Illustrator. Especially if I have multiple Adobe programs open at once, like Photoshop + InDesign (one morning before class it "froze" 3 times on me while I was preparing a presentation). Sometimes It happens just with video streaming + multiple other browser tabs! And I've been keeping logs, starting a timer whenever I open these power hungry programs. This "freeze" will happen anywhere between 3min and 3 hours! It's not something I can ever expect when it happens, I just save often and hope for the best. Sometimes I'll, say, open WoW, I get a freeze within 9min. then I restart try again, and it's fine for 3 hours! One last thing I have noticed, is that this problem doesn't seem to happen if I only use the laptops onboard keyboard and trackpad, not really sure though because I don't use it often. Even so, I've been using the same logitech mouse and keyboard (with no logitech support programs) for over 4years, and for the 1st whole year I've had this Macbook this never happened. What have I done to try and stop this? I'll start by saying I have not upgraded to El Capitan and am still on OSX 10.10.5. So before going to the Genius Bar this is everything I did: Virus Scanned W/ ClamXav PMC Reset SMC Reset All programs and plug-ins updated (Java had not been auto updating) Disk permisions verified and repaired Disk verified and repaired OS X Reinstalled Apple Diagnostics Checked No problems Found Disk Erased and OS X Reinstalled All resulted in nada, problem persisted. Doing all of the above is supposed to point to a hardware issue right? At least that's the theory we were going with. But ONE MORE strange thing, I tested the issue out in Bootcamp, playing Skyrim on Windows 7 for a little bit...the external controls never froze up like the mac side, but every couple minutes they would stop working for about 5+sec, then start working again...almost like they disconnected for a moment. So at this point I've taken the thing to the Genius bar, I showed them everything I've done and the guy just says "we'll send it off to the repair center." He then runs one little boot-up test of some kind (something about connecting to a network in the store) and there was an error that he says definitely suggests a GPU issue. Computer then get's sent off for 5 days...and they replace the logic board, not the GPU (oh and the screen lighting is kinda messed up on the bottom, but that kinda fixed itself...?). I think everything is fine, take it home and go about my business...2 hours later the lock-up happens. And that is basically my story so far. Atm I just have to deal because I'm in design school, and I simply cannot be without my computer for another 5 days until December. If anyone has any ideas I would LOVE to hear them. I've tried looking at System Diagnostics in Console, but I really don't understand any of that stuff lol.