My computer, a 2013 MBPr 15" 2.3GHz, has had a persistent issue with undervolting my CPU and GPU when the temperatures hit between 95° and 100° C. And as much as this is normal, and to be expected of any motherboard when determining that the temps of its components is too high, I remain unsatisfied that I cannot fully saturate my CPU and GPU while retaining the clock speeds as advertised by Apple itself. So, having had a similar issue with my previous MacBook Pro, and having fixed it by replacing the thermal paste myself, I brought my computer in to the Apple store for this to be done. I was dismissed as uninformed and paranoid under the argument that there was no issue. The “Genius”, admitting to not understanding anything about the issue I was presenting, ran only the diagnostics available to him, which told him that the computer was running fine. Which is to say that the computer was not malfunctioning. But of course it isn’t — the system is throttling the internals to ensure that it doesn’t malfunction. And throttling itself is a core function of the machine. Nothing was actually “wrong” with the machine because the logic board scales back its voltage to prevent anything from being wrong. In other words, the computer is designed to underperform due simply to the quality of the cooling system available to it. When I escalated the issue to their “Lead Genius,” I was told unequivocally that the CPU can run comfortably at 120° C. and there was no issue. Both Apple Tech Support and Intel Tech Support later clarified that it can, perhaps, hit 120° for an incredibly brief period, but that instability is to expected at 100° and higher. I should also mention that I was asked if I meant “degrees or Celsius” when referencing the temps, and was told that 120° C < 200° F…… I understand that I have a responsibility to provide the computer the best opportunity to work as efficiently as it can. But provided that I keep the computer in a chilled environment, well-vented, and clean, there is no reason for me to not be able to leverage the full base power of both the CPU and GPU, and I simply can’t. My GPU clock speed occasionally drops from 925 MHz to a low point of ~600 MHz. My CPU will dip as low as 1.5 GHz when it hits 100° C, and slowly climb, then dip; then rinse and repeat. If I am conforming to Apple’s specifications regarding an optimal environment for this thing to work as advertised, it should work as advertised. But when I have to fight tooth and nail to get Apple to recognize not just that the computer is performing sub-optimally on a consistent basis, but that such an issue is not okay for a $2200 machine, then we all have a problem. I know Macs run hot. But what’s par for the course shouldn’t define the gold standard. And in truth, I don’t care how hot my computer gets. I only care that I get the performance I was promised.