Hi all, My faithful 2012 15" MacBook Pro is acting a little bit strange. I first noticed it really being sluggish in Final Cut Pro X a little while back, but since my project was really large, I thought that was the cause of the sluggishness, but it is not as I recently found out. My laptop seems to actually be clocking itself to exactly half of the CPU's advertised clock speed. The CPU is a 2.6 GHz i7-3720QM, but it actually is clocking itself at 1.3-1.4 GHz while in OS X. I thought this was really strange. I used the Intel Power Gadget to measure the CPU clock in OS X and used the Intel Processor Diagnostic live USB to measure it in Fedora while booted off of a USB drive. In OS X, the clock speed is stuck at that 1.3-1.4 GHz point (screenshots attached) but in Fedora, the clock speed is 2.63229 GHz, normal for the CPU. The first thing that I did after checking the clock speeds was to check CPU temps, but the Intel Power Gadget and diagnostic test reports 45-50ºC, again normal for the CPU. Next I checked the battery, which reports a normal condition. It is well known that a bad battery can cause halving of the clock speed, but that appears not to be the culprit here. After checking the battery, I reinstalled OS X on a separate drive to rule out a software issue. No dice. Clock speed is still 1.3-1.4 GHz. I work in IT for a school district that is an Apple SSA, so I ran ASD next. Completely passed both the EFI and OS diagnostics with flying colors. What??? I think I'm going to drive myself crazy trying to fix this, as I am a video editor/programmer and a little bit higher clocked CPU can really boost performance in those areas, so doubling the CPU clock could do me wonders. Does anyone know what is going on here? Thank you for any help you can give!