iMac vs custom built PC for photo/video editing

As a 13" Macbook Air and low end desktop PC owner, it was time for me to upgrade to a more serious platform for photo and video editing.

With limited onboard storage, the Mac Pro was not an option.
My choices were the 27" iMac (either regular or 5K), a custom build PC or a Hackintosh (more on that here: http://www.tonymacx86.com/ ).
The Hackintosh did appeal to me but it would have restricted my build to very specific parts. I would have installed Windows anyway as a few softwares I use are not supported by OSX, so I ruled it out.
I felt the non-5K iMac would not be powerful enough for my use, and a maxed-out 5K iMac would run too expensive. So I built my own PC.

To compare the specs, here is a show-down of each option.

• The 27" non-5K iMac I considered was the 3.5Ghz i7 (3.9 turbo) with 16GB of Ram, a 3TB Fusion drive (which combines a 128GB SSD and a 3TB hard drive) and the GTX775M graphics card. As of February 2015, this costs just under €2800 or £2050.

• The 5K iMac with all the available options is close to my current setup. It uses the same i7-4790K CPU running at 4.0Ghz (4.4 Turbo) with 16GB of Ram, a 3TB Fusion Drive and the AMD Radeon R9 M295X 4GB graphics card. This runs at €3450 or £2550

• The PC I built is based on the i7-4790K processor, 16GB of 1866Mhz Ram, a 256GB SSD + 2 x 2TB 7200Rpm hard drives and the GTX970 4GB GPU. I will upgrade it to 32GB of Ram and will add a 512GB SSD. With a Windows 7 licence and a few accessories (optical drive, SD / micro SD card reader, high end CPU cooler, quiet case fans, mid-tower quiet case (Fractal Design R5)) and a 27" 1440p IPS display, it costs around €2200 or £1600.

The GTX775M is benchmarked at 4530 points ( http://www.videocardbenchmark.net/high_end_gpus.html ), the R9 295X 4GB scores just below 5000 and the GTX970 4GB tops at 8603 points. Do not confuse the mobile versions of the graphics cards used in the iMac when reading the chart. The R9 M290X gets a score of only 2547 while the desktop 290X card reaches 6875.

The main goal of going high-end was to speed up the operation when photo and video editing.
I use the Adobe suite (Lightroom, Premiere Pro and After Effects) and their softwares are fairly optimised. Both Premiere Pro and After Effects use GPU accelerations to speed up rendering times, this is why I went for the GTX970 graphics card with lots of CUDA cores and Vram.

Two months later, here are my thoughts:

• Choosing the parts and building the PC was an interesting experience. It certainly was way easier than I thought and I learnt a lot during the whole process.
• I enjoy the upgradability of my system. I can re-use hard drives from my previous PC or setup a RAID array very easily. If the graphics power ever becomes insufficient, I can always add a second graphics card in SLI and double the graphic power.
• I tried a few games in Ultra, all run very smoothly ... except Flight Simulator X.

Here is what I did not expect:

• Despite choosing quiet fans and a quiet case, the PC is nowhere near quiet even when idling.
• Flight Simulator X still struggles at times. I use it when coaching some of my flying friends and it is disappointing to see that even this high-end system is not powerful enough without over-clocking the processor. Most scenes are more than fine but a highly detailed New York city in ultra settings will kill it (down to 15 fps in 1080p).
• Coil whine. If you've never heard of it before, have a look on youtube. It is a high pitch electronic noise and is very audible.
  Both my graphics card and the power unit suffer from coil noise and it is extremely annoying. This alone makes it worth getting a much more pricey and slower iMac. Fortunately, it only happens when stressing the GPU (when gaming). 
• Boot times are nowhere near as fast as my Macbook Air. Windows vs OSX...
• I miss a lot of features from OSX that simply don't exist under Windows. 
• Windows can't display raw (.CR2) photo files natively, OSX can. Big deal for photographers who shoot raw.
• Photo editing with Adobe Lightroom 5 is actually not a lot faster than on the much lower-end Macbook Air. On the go operations like clarity or tone curves are fast on both systems, the Macbook Air slows down a lot when making finer adjustments like spot removal or using the adjustment brush ... and so does my custom built PC. It is not as slow but it certainly is  slower than I expected. Zooming used to be very slow on the Macbook and it is not a lot smoother on the PC. A big disappointment is that the PC is not faster than the Macbook Air when it comes to exporting files. Photographers that retouch hundreds of photos at once hate to wait sometimes up to 10 minutes for Lightroom to export their images. I simply see no difference between my 1.3Ghz dual-core Macbook Air and my 4-core / 8-thread 4.0Ghz PC. Surprising...
• Adobe Premiere Pro.
  Believe it or not, my low-end Macbook Air can run Premiere Pro and edit 1080p video files. It is slow but it works. In fact, most of my videos up to now were edited on a 4 year old low-end PC with Sony Vegas. You do not need to spend a lot of money on your PC if you want to edit videos. But you will need a lot of patience. My 10min "Life as an Airline Pilot" video took 5 hours to render. It would take my new system less than 10 minutes to render it.
  Now this is where my custom built PC truly excels. Everything is very smooth, there is no lag even when non-rendered edits are played-back in their original size. I've seen Adobe Premiere Pro running on a high-end iMac and there is no comparison. The custom build is simply much faster and much smoother.

Knowing all this, would I go for the custom built PC? The honest answer is ... no.
Unless your job is to edit 4K videos, the iMac is more than enough.
For a similar price, an iMac would be well lower-spec'd than a PC. If you're spending €2000 / £1500 on your system, it will run most programs you throw at it with no hiccups. Sure, it might take longer to render your heavy video files but you'll save on startup times and less software bugs.
Now, if you're a serious gamer, you already know that Macs aren't for you.