water cooler fan

How fast is the fan spinning? I recommend the Corsair SP120's as they're high static pressure meant for radiators. Get the high performance one in case you need the RPM speed for cooling.
Keep in mind that any fan, once turned up, will make noise against a radiator.
Those corsair fans move more air than most fans at lower rpm, so it should be a lot more efficient for you and quieter.
 
my rad fan at min spins 672 and is quiet dut at 100% its 2311 and quite noisy

i will look in to the sp120s as i have 2 af120s in my case one on top pushihing air in and one at the rear for exhaust
 


Yeah the AF's are made for open air like you're using (I use an SP at my bottom just so I can bring in a lot of air if needed and it works great as an intake as well).
Again, any fan will be noisy spinning at > 2000 RPM. The high performance SP's can go up to 2500 RPM and make noise at that speed. The goal here will be that you should be able to get the same performance as your current fan by spinning the SP120 a lot slower, so that will make up the noise.
 


If you have the room to do that, then go for it for sure. Those two fans will move a lot of air at low RPM, so they should stay quiet.
 


I have built a system with an h80i and Corsair SP 120 (performance editions). DO NOT EVEN CONSIDER THE QUIET EDITIONS, THEY MOVE ZERO AIR. At idle the performance editions are noticeably quieter than the stock fan, but at load, they are about the same to be honest.