A lot of the photography that I do is done in my informal studio, with my camera(a Digital Rebel XS) clamped on a tripod. As a result, I almost always tether the computer to my camera and control it using EOS utilities. I use live view mode, and effectively never touch the camera once it's set up-I adjust shutter speed, focus, and everything else from the computer. Since switching to Macs a few years ago, I've noticed that EOS Utilities seems to be a big resource drain on my computer. Any time I'm using it, the fans rev up to full blast, the CPU usage gets near 100%, and if the computer isn't plugged into outlet power the battery will drop about 1% every minute(I normally get several hours on a charge). My computer(13" MBP) shipped with 10.7, and I'm currently running 10.9. I initially was using the version of EOS Utilities that came with the camera, but have downloaded the most up-to-date version that will work with my camera. Nothing has really changed. Not too long ago, I started picking up cheap PowerPC laptops. I set all of them up with EOS Utilities just so that I could grab whatever laptop I wanted and use it. I installed the version that came with the camera, and all the PPC laptops I use are running 10.5.8. I don't think there's a more up to date version of EOS Utilities for these. Interesting enough, the program feels very "light" on these computers, despite the fact that they are in every way inferior to my Macbook Pro and every other Intel based computer I have(a couple of Core2Duo based Macbooks). My 12" Powerbook(1.5ghz PPC G4, 1.25gb RAM) has become more or less permanently tethered to my camera, at least for use on the tripod, and it doesn't break a sweat doing the same tasks I use to do on my MBP. The CPU temperatures stay manageable, the fans barely run, and the CPU usage stays well below 50%(which is more than I can say for browsing the internet on this computer). Has anyone else noticed something similar with these combinations of components and software?