This was my third PC build and the toughest of them all. The Legacy U2-S case is beautiful but extremely hard to build in, especially if you have a large heatsink.
Dual booting OSX Yosemite and Windows 10 and everything runs smooth, no issues with heat whatsoever even during long gaming sessions. Best of all, with only 2 Noctua fans using the ULNA's, this thing is super quiet, can barely hear it even on full load.
Case: Rosewill Legacy U2-S Silver/Aluminum ITX Case Fan: Noctua NF-S12A Motherboard: Gigabyte H97N-WIFI CPU: Intel Core i7-4790 Cooler: Xigmatek Dark Knight II with Noctua NF-F12 Fan Memory: Adata XPG 16GB DDR3 1600mhz HDD: Samsung 840 Evo 120GB SSD, Samsung 840 Pro SSD 128GB, WD Green 1TB Graphics: Zotac GTX 970 4GB Power Supply: CoolerMaster V550 80 Plus Gold Semi-Modular (550W) Monitor: Acer S277HK 27" 4K IPS (recent upgrade) Dimensions: 12.56" x 8.19" x 9.17" (H x W x D)