The i7-3930k is a very easy CPU to overclock and my first recommendation is to get the Asus Rampage VI Extreme motherboard , it will make the overclocking much easier.
I have both of these components and the 3930k is currently clocked at 4.5ghz with Idle temps in the mid 40c and when stress tested the temps went to low 60c, high 50c.
Also the three video cards are water cooled by a separate radiator and under full stress at full ultra settings with a 2560x1600 monitor they topped out at the high 40c. I used Uniigine Heaven Benchmark DX11 Ultra settings and normal Tessilation and 4x AA.
I have a custom water cooling set up but what's cooling the CPU and motherboard is a 240 radiator with double fans so that is comparable to the closed loop coolers that are being sold. If the fans are too loud then change them out for better low noise fans , you don't have to keep the fans that came with the unit and it's cheaper to change fans then get another unit.http://www.newegg.com/Product/Product.aspx?Item=N82E16835181021
21db is quiet and has a high static air pressure for better air flow.
The ACX cooler on the Evga video cards will keep the cards cool and quiet.
If you have the money then a custom water cooling is the way to go as you can pick your own parts and get really good cooling power from a wide choice of radiators and fans.