Finished the build (i7 5820k, Noctua Nh-D15, Asus x99 deluxe, 16gb 2666 ram, Asus gtx980 Strix, Samsung 850pro 256gb, Silverstone FT02). The GPU stays at 40'-44' / 0% fan in idle and 70'-75' / 50% fan during 3dmarks and heavy gaming at 1440p@ultra (and hardly audible while at it; however setting the GPU's fans manually at 60% increases noise greatly, at 80%+ it turns into intolerable shriek). Guess I won't risk overclocking but at stock it seems pretty viable.