Reducing HSF Air Flow

[nodoze]

The HSF used on the Swiftech 462 provides 68CFM to the HS which cools down the CPU very well, but it comes at the price of 48.5 dBA which is way to loud for my ears. I was thinking about replacing the fan with a quieter one. I realize that this means I have to give up some CFM and that my CPU temps will rise but I'd like to know how much they will go up.

Is there a general rule of thumb that could tell me that reducing the CFM by X% will raise the CPU temps by Y% ?

[XprincoX]

Here's a lil article Ed did awhile back ago that may help: http://www.overclockers.com/tips457/ :D

[Yodums]

48dBA isn't that loud it's pretty identical to the Delta 38, 46dBA.

You can't replace if with any really better unless a Delta 50.

The Swiftech need those top notch Delta so they can actually keep up the with the heatsink.

For the 68cfm One you can try 7v it.

Yodums

[Hoot]

Yodums is right:

There is more to that fan that makes it worthwhile other than just the cfm. The de-spiraling vanes improve the quality of the air-flow from it. You would get better performance from it at a reduced voltage than replacing it with a slower, conventional fan, running at full voltage. I have an MC-462 and have run that fan on a rheostat. Even at a restrained speed it does an excellent job removing the heat from the heatsink.

73, Hoot

[nikhsub1]

Well I have the MCX462 as well and couldn't stand the noise either. I swapped the delta for a 50 cfm Sunon. I see about a 4c difference in temps with the slower speed fan. The delta is thicker than the sunon so what I did was I used the stock fan screws which are very long for the sunon, and screwed them in about 2mm and then pulled the fan away from the sink, about an inch. This helps and seems to cool better than with the fan directly on top of the sink. I see 36-39 idle and 43-45 load, not great but quiet!