Fan Speeds

I've just changed the case fan on my tower from a noisy 90 mm fan to a quiet running 80 mm fan. Now I've heard that some of the quite fans run slower and therefore don't move as much air etc. so I'm slightly paranoid that I've lost alot of cooling power.

After downloading Everest yesterday I monitored the fan speeds and temp on the case and motherboard (which I assume is the CPU sensor?)

Case fan speed - 2300 rpm Temp 38 C (100 F)
Mobo fan speed - 5500 rpm Temp 48 C (118 F)

Now, if I'm right the temp is no problem but is it normal to have such a difference in fan speed? Is my Mobo fan going nuts? and finally, can anyone confirm that the Mobo temp that I'm getting from Everest is the CPU temp or should I check some other way, if so. How?

Thanks for the help. Sorry if the answers are obvious to you all but I'm new to this and probably shouldn't be fiddling anyway... I just got tired of sitting next to something that sounded like Concord taking off...

 

i'd guess the 38 degress is your case temp which is borderline on the warm side,download and run this program

http://majorgeeks.com/Toast_d867.html

the one that rises fastest is your cpu. you should try and keep it around 50ish and your case temp around 30ish.

 

Thanks Rikky.