i got the stock fan on my HS... 4600RPM... works fine for me... and it's whisper quiet.
It's the newer model Taisol but so, it's a little better than their old ones.... it's about 3 to 4 inches high off the mobo and uses the 3 clip thing... can't remember the model number..
If you are getting temps in the 50+'s then i can EASILY diagnose your problem. Either your room temperature is too hot (ie. Open some windows or get some ventillation). If your room is about 25C then it shouldn't be that that's affecting it coz that's what mine is around... Next thing is that you might need to ventillate the case a bit better. What size case do you have? If you keep it all closed it will get really hot really fast. What you should do is just open the case up, take the sides off, and what i do is open the free drive bay slots and the PCI slot covers and it just allows for totally free movement of air. Failing that, keep your case on, but get some serious case fans going. If all else fails, get some Arctic Silver II thermal paste and make sure you put it on properly. A thin layer will usually do, make sure it's no thicker than about 1mm so that you get the optimal heat dispersal from your HSF.
If all else fails, get water cooling
<b><font color=blue>Who needs drugs when you got <font color=black><i>BasS?</i></font color=black></font color=blue></b>