WoW is much more cpu intensive than gpu, especially once it come to large 20+ ppl raids. I'd also recommend going with a r9 380 over a GTX 960 in a general gaming rig, but the Nvidia drivers are better optimized for WoW.

Even if you guys don't know or what overclocking is, WoW is one of the few games that really benefit from it. Not only is going to give you better performance, but it's also going to stay relevant for an extra year or two when you compare it to an i5 6500. Here's an excelent Skylake overclocking guide.

I'm going to recommend two builds since you have a good budget to give you a few options.

First build is a 6600k / GTX 960 running on a 25" 1440p IPS monitor.

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