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The windforce cooler is fine at idle. 45% and it's the loudest thing in my pc but you can live with it, 60% and it's obnoxious. If you plan on overclocking, have high ambient temps, poor airflow in your case, the fans will spin up.
The KFA2 cooler is extremely quiet even under load, but it gets hot. The reference style coolers from EVGA are just noisemakers, have a look on the EVGA forums and reviews. I've not had any experience with the DC2 but I heard good things.
They are all pretty quiet till they aren't. Don't take people's opinions as truth, do the research and if worst comes to worst DSR it and eat the £9.75 postage costs.