My 240mm H105 keeps my overclocked AMD FX 8320 at 24-32c idle and 45-52c Max while gaming even on the hottest day. It's a 3.5ghz 8 core cpu and I have it overclocked to 4.8ghz.
But I am using 4 fans on the radiator in a push push pull pull configuration. 2 inside the case pushing air up through and 2 on top of the radiator pulling air up through. BUT I run the fans at 6v so they only turn 1000 rpm max. With 4 running I still get 72cfm of pressure per pair but they are dead silent. The original Corsiar fans were loud as hell even running off of 6v because they are a dual ball bearing type fan.
The fans are nothing special, just some cheap Cooler Master SickleFlow 120mm fans. I bought 40 of them on Black Friday a few years ago for $3.95 each. They work good but I can tell ya that they do not last. I had 2 that the bearings were noisy in rite out of the box. The ones I have are the 1st generation single ball bearing fan. The new SickleFlow fans have a rubber O ring to keep the dust out of the bearings. They are around $10 each on newegg $7.50 each if you buy 10+. I can't afford the the good Noctua 120mm silent fans. Those things are around $40 each but they are the best fans that you can get.