I wouldn't go with the suggested builds here, way overkill/overpriced & too loud.
PCPartPicker part list /
Price breakdown by merchant /
Benchmarks
CPU: Intel Core i5-4670K 3.4GHz Quad-Core Processor ($219.99 @ Newegg)
CPU Cooler: Noctua NH-U12S 55.0 CFM CPU Cooler ($62.99 @ Mwave)
Motherboard: ASRock Z87 Pro3 ATX LGA1150 Motherboard ($94.99 @ Newegg)
Memory: Mushkin Silverline 8GB (2 x 4GB) DDR3-1600 Memory ($69.97 @ NCIX US)
Storage: Samsung 840 EVO 120GB 2.5" Solid State Disk ($89.00 @ Amazon)
Storage: Western Digital Caviar Green 1TB 3.5" 5400RPM Internal Hard Drive ($64.98 @ OutletPC)
Video Card: Asus Radeon HD 7850 1GB Video Card ($134.98 @ Newegg)
Case: Fractal Design Define R4 (Arctic White) ATX Mid Tower Case ($101.98 @ Best Buy)
Power Supply: SeaSonic 520W 80+ Bronze Certified Semi-Modular ATX Power Supply ($73.99 @ SuperBiiz)
Total: $912.87
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-01-27 22:21 EST-0500)
1) There's no better CPU for WoW than the 4670K
2) I've added a NH-u12s, a NH-d14 isn't needed at all and stick to aircoolers. AIO liquid coolers aren't quieter than aircoolers and they tend to have lots of issues.
3) That board is all you need, anything expensiver is a waste and they don't perform a tiny bit better.
4) 8GB ram is all you need
5) Added the 840 evo 120GB, if you think you need a bigger ssd then go for it
6) The green drive is just all you need, 7200 rpm's dont perform noticeably better and they make a lot more noise. Get a bigger one if you need it.
7) A 7850 would just perform the same as a 1000$ gpu in 25m raids/40 vs 40 bg's
8) Cooler master haf x cases are crap, extremely loud and awful build quality. Took a R4 instead which is quiet optimized and the build quality is superior over any other cases for the price. You can take a windowed version or a different color, up to you.
9) Usually 430W psu's dont have the correct amps on the 12V rail, but the 520W I took does and it's a seasonic :P
I wouldn't go with a 38" 1200p monitor/tv really, that's pixel counting.