Actually, the best 'bang for the buck' would be to get an old used Mac Pro 2010 model with two Xeon processors preferably the lowest clocked ones and upgrading both to the 6 core X5690 processors @ 3.47ghz, effectively creating a 12 core machine with hyperthreading. These can be had on ebay for about $250 USD each on eBay. A baseline dual processor 2010 Mac Pro should sell for around $1,500 USD (depends on additional components and RAM of course). Throw out the old processors (sell them on ebay, but I doubt anyone will be buying them unless you ask for a bargain price). With this, you can add any GTX card you want and play games AND do rendering the right way.
You're total will come out to around $2,000 USD for a 3.47ghz, 12-core x5690 Westmere system (minus a new GPU). You're geekbench score will blast any new trashcan Mac Pro with final score of about
32,000.
If you wanted to penny pinch or break it down for VALUE, this means each geekbench point's cost is 6.25 cents.
If you did this for the new Mac Pro quad core, priced at $3,000 with a geekbench score of 14,326, then it's cost per point is 20.9 cents (ripoff). For your iMac configuration the core i7 4790k with the r290x GPU with a geekbench score of 16,545 @ $2,549, you're looking at 15.4 cents per point.
Just for comparison's sake, my Hackintosh cost me $1,300 USD (4790k, GTX 960, 32GB RAM 1866mhz). Geekbench score of 18,041; cost per point is 7.2 cents. Since I can overclock it and get up to around 22,000 points, the value then become 5.9 cents per point. However I am not running it overclocked but to compare it to the Mac Pro, I have some gains;
- I can swap any part I want for something better, newer, etc.
- I'm only using ONE processor, so its more efficient
- I have full SLI compatibility in Windows
- My system runs just as quiet as the new trash can Mac Pro (seriously, I can't hear it at all)
- It produces WAY LESS heat. This is a freaking GODSEND in the summer. My old Mac Pro 2008 and 2006 got pretty
toasty, I can only imagine what the x5690 processors do to a small condo or room. No need to run the AC all the time.
- GPU choices will run circles around any new Mac Pro GPU and especially the r290x.
If you need geekbench scores for proof, click here:
https://browser.primatelabs.com/mac-benchmarks
They're not exactly 100% accurate, but geekbench is good enough to gauge a systems performance and value for the money, so its a great standard.
So there you go, neither the new mac pro or the new iMac is worth your money, both are duds for the money and you're best option is either the cheesegrater Mac Pro or a Hackintosh, because what your current two choices for gaming are absolute garbage. But what you do with your money is your decision, but know this;
We're giving you advice based on LOGIC, RATIONALE and OBJECTIVITY.