In my endless efforts to keep the s5 cool and quiet running near default speeds, I have opted for Noctua and Arctic cool fans. Those fans that you posted are not that quiet. The 35db is not that quiet. Unless they are PWM fans, they will be running at full speed. What you are looking for in a cooling fan for the s5 is one that directs more of the airflow forward than just spinning fast. The Noctua fans are designed to push air in a more forward direction. I have tested this and it is true. My Noctua fan on the front pushing air in is a Noctua industrial 2000rpm PWM fan. It is currently spinning at 1680rpm and an Arctic F12 PWM fan running at 1200rpm. Combined with the miner set at 325 they are making 44db in sound. Temps are 60 and 62c with 17 hardware errors over a four day period, ambient temps in the 20-25c range.

I tested a higher cfm fan at the same settings as my push fan with the temps running into 65-70. I also had to add a fan to the rear of the miner to push hot air away from the miner, one fan on the side of the miner to push air into the top of the miner (my miner sits on its side) and one fan on the bottom pulling air away.

So you see, long story short... It is the design of the fan and how the fan pushes the air that makes the biggest difference. If I disrupt the airflow of the Noctua my temps will go up and the Noctua will spin faster. With that said, I recommend the http://www.amazon.com/gp/product/B00KFCR5BA/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1 and the http://www.amazon.com/gp/product/B00H3T1KBE/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1