Hey everyone, I'm posting here in order to get some advice on what has been an extremely frustrating ordeal for me. So, back in October/November 2014, my beautiful late 2013 (16GB RAM, Intel i7, everything maxed out) iMac's fans started behaving very strangely. The fans would spin up to full speed when the machine was doing nothing, Activity Monitor reported 2% CPU load, and iStat reported that temperature readings were fine. More strangely, early in the morning, after the machine was sleeping all night, the fans would spin up all by themselves, spin up, spin down, spin up, and continue until I shut down the machine (this isn't pleasant at 5AM when you're trying to sleep). Naturally, I tried a PRAM reset, SMC reset, nothing. I started noting that the problem happened in Windows (gaming partition) as well, which ruled out driver/software issues. The machine was (and still is) in warranty, so I immediately took it to the Apple Store in the Westfield (Southland) shopping centre here in Melbourne, Australia. When I got there, they did the typical tests, and the machine apparently did not return any errors. I noted that the fan issue is very random and happens without any warning or pattern. They said that they'd take the machine in and monitor it, and that it could be the fault of a USB 3TB hard drive that I use as a Time Machine. They also said it could be a software issue. I noted to them that it can't be a software issue since the issue is also happening in the Windows partition. They said that Windows uses 'the same drivers' that Mac OS X uses, and that if the Mac drivers are corrupted/faulty then the Windows drivers will be faulty, which I know is complete crap since you can't write a Mac OS X driver and expect it to work in Windows, and Apple writes their own Boot Camp drivers for Windows which are separate from the Mac OS X drivers, but I didn't really argue the issue much since I wanted to get the computer fixed ASAP, so we agreed that they'd monitor the machine and get back to me. I was confident they'd be able to replicate the issue and then fix it (software issue or not). Anyways, they got back to me about a week later and said that they could find nothing wrong with the machine, they couldn't replicate the issue, and thus they asked me if I wanted to take it back and troubleshoot it myself so I could check if indeed it was a USB device that was causing the problem. I agreed. I took the machine back. As soon as I got it back, I discovered I started getting the problem again. Indeed it was caused by USB devices, but not just my 3TB hard drive, but any external hard drive, with our without a power supply. More interestingly, the problem would persist after a while even if you unplugged it. This time, I recorded videos, took screencaps of iStat showing the machine was making the fan run at 4000rpm without any strange temperature readings & Activity Monitor saying that the machine was at 1~2% CPU usage, etc. Took it back to the Apple Store. This was my third visit (one to drop off, one to pick it up). This time the person was really understanding, checked out the videos, said that yeah it was obviously the hardware, and didn't try to concoct any such things as Mac OS and Windows using the exact same drivers, etc. So far so good. Got a call later that week saying that he replicated the issue while the machine was in firmware OS selection mode, he said he replaced the logic board. Went back and got the machine, then took it home. The bluetooth keyboard won't connect. After I get a USB keyboard to get the machine to boot (since it won't boot without a keyboard), I realise that I can't get the machine to pair with any bluetooth device and that the bluetooth is now broken. The same Apple wireless keyboard and mouse pairs fine with my old MacBook. This is where things start getting frustrating. The next day the machine refuses to boot *at all* (verbose boot says that the Mac HD volume can't be repaired after an FS check, and that it's broken). Didn't even bother trying to boot to Windows at this point (I think the recovery partition also reports it's unusable anyways). I call Apple Support. They tell me they'll arrange something, and that I can drop the machine off tomorrow at anytime. The next day, I drop it off. At this point I'll note that I don't drive so each time I want to visit the Apple Store I have to haul the aforementioned iMac through public transport, which is not ideal since I don't feel comfortable carrying a $2000 machine through Melbourne's train system. Anyways, when I arrive (5th visit now), the Apple Store's 'Head Tech' person greets me, proceeds to tell me how it'll be another 5 days because they don't have the bluetooth module on them, and how they need to check that it's a software issue (again) because it could be 'corrupted drivers'. I try to (politely) explain that this can't be the case because Windows is broken too, blah blah blah, she proceeds to explain to me the same stuff about how apparently Mac OS X and Windows use the exact same drivers. She says she can't do anything until they've diagnosed the system and that I'll have to wait until the new part ships in. No empathy or anything over the fact that I have been without my computer for probably a good month now and that I have *work* which unfortunately needs to be done in that exact machine (as it's the only Mac OS machine I have with recent specs, I do freelance design and app development for the iPhone). They also don't seem to care that I am a registered Apple developer, that I know what I'm doing, and that I know the Mac OS back to front and that *I know* it's not a software issue, and they choose to ignore that, and regurgitate the same stuff (which to the best of my knowledge I know is wrong). I've been coding and troubleshooting my own software problems across all three major OS'es for a good 7/8 years now. And, of course, I've been unable to work because the machine is broken and I have deadlines to meet. Anyways, should I be complaining to some of the higher-ups here, or is the Apple store behaving reasonably here? I'd ideally just like a new machine instead of having the current one break after they've 'fixed' it. I fear there's some dodgy component in there that is frying other stuff in the machine, the latest Apple tech agreed with my concern, but they won't replace it. Barring that, some free AppleCare or something so I can keep sending the computer for repairs sounds reasonable for 5 visits to the Apple Store and a month without my machine. I'm rather disappointed in the sub-par service, normally Apple's service is top notch and that's why I'm happy to fork out the extra $$$ for a machine which I know will be reliable and won't let me down. Also, if someone familiar with Boot Camp drivers could confirm or deny the Apple employee's statement that the Windows drivers are merely there to interface with the Mac drivers, that'd be awesome. Knowing how drivers work, I call ********, but it's best to give them the benefit of the doubt I guess. Thanks a lot everyone.