As the title states, I’m trying to decide between keeping the RiMac in my signature (4Ghz, 295MX) which I’ve owned for just over a year now and am very happy with, or selling it and keeping a 6 Core/D500 nMP which I picked up on Cyber Monday for cheap. I primarily use my computers for: 1. Photography (Aperture/Pixelmator, at some point switching to either Capture One Pro, Lightroom, or something else) 2. Media Processing (mostly transcoding Blu-rays via handbrake, managing my media library in iTunes and other apps, and occasionally working with iPhone/DSLR Video) 3. Gaming (Dolphin, Mac/PC only games, and games where the Mac/PC version is superior to the PS4 version) 4. General web browsing, document preparation and content consumption My current thinking is as follows: CPU: The iMac’s 4Ghz Haswell CPU, has a one generation architectural IPC advantage, a 500Mhz faster base clock, and can turbo up to 4.4Ghz when not thermally limited. In single or lightly threaded tasks (four threads or less) the iMac will be significantly faster as has been demonstrated by benchmarks from around the web. The Mac Pro of course has six cores however, so for heavily threaded tasks/ heavy multitasking it should win out by around 20-30%. Winner: iMac Outside of transcoding blu rays, as far as I know my other two heavy hitting use cases, photography and gaming are not particularly well optimized to take advantage of more than four cores/threads (feel free to correct me if you think I’m wrong) GPU: The iMac’s GPU is equivalent (albeit newer design wise) to the D700 Mac Pro card and thus significantly faster than a single D500. For apps where both GPUs come into play the Mac Pro should obviously annihilate the iMac but although I’ve heard Capture One makes good use of dual GPUs (which it should as it ran like dog **** when I tried it on my iMac), I’m not so sure about Aperture, Lightroom and other RAW converters. For gaming in OS X (almost) no games use Dual GPUs thus the Mac Pro would be a big step down. For gaming in Windows, games that support Crossfire would see a large performance boost but it seems like recent games are moving away from design models that supports Crossfire/SLI, so that kind of negates this point. On the other hand the D500s can (maybe) be overclocked and won’t fry an egg/sound like a hair dryer/throttle when under heavy load. Winner: Undecided If my primary productivity apps could make good use of both GPUs and provide a significant speed up in OS X then that might give the edge to the Mac Pro. That said the performance drop in single GPU gaming/applications would be hard to swallow especially in OS X. Screen: iMac has a 5K screen built in. Mac Pro would require me to procure 4K screens. Winner: Clearly the iMac as I don't have to buy an expensive screen(s). As you might guess I’m leaning towards keeping my iMac and just selling the Mac Pro (I bought it on impulse because the price was so good), but I’ve really fallen for the design, have always wanted a six core machine, and would love for someone to help me find a reason to keep it. One final note, the iMac has Applecare through 2017 whereas the Mac Pro is out of warranty. Of course with Skylake, FinFIT GPUs, and Thunderbolt 3 on the horizon this year, I may well end up selling them BOTH by the end of the year but in the meantime I need something to use If you read this far, thanks! Thoughts?