"Not too heavy"... so I guess single towers
Do you have a thin AsRock board that flexes?
high end ~$60-80: Noctua NH-U14S , Thermalright Archon , Prolimatech Megahalems
--> Noctua U12S, Prolimatech Armageddon if you have a case CPU cooler height limitation
mid end ~$40-50: Thermalright Macho , Thermalright Macho 120 ,Thermalright True 140, Thermalright True 120M , Alpenföhn Brocken 2 , Deepcool Gamer storm ( Alpenföhn Matterhorn)
low-midend $30-40: Silverstone AR03 / AR01 (both are louder than the above , i.e. bad fan ... 2200RPM max), NZXT HAVIK 140 / HAVIK 120 (subpar fans, overpriced)
If performance isn't THAT important (a few degrees difference):
high-midend ~$50: be Quiet Dark Rock 2 , for aesthetics ; Phanteks PH-TC12DX (less quality control than the larger PH-TC14PE ; fan spins to 1800RPM)
Which country are you in?
Thermalright's Macho , Macho120, True 120M are all getting nickel plated better looking versions coming soon, for the exact same priceEdited by AlphaC - 11/9/13 at 8:42pm