PII cooling fan question

[lorlabnew]

Hope this question isn't too silly;

I just replaced fan on my old PII400 CPU (in SECC1 cartridge). While checking the fan functionality, I noticed it's blowing into the heatsink (I always somehow thought it's opposite). It seems to be working fine, since cold air rushes through all those grills there and blows out on the sides; it just surprised me... Btw, this was the only way how to attach this 50mm fan (which I removed from other SECC1 heatsink of a slightly different model, since mine was more massive and I wanted to keep it). After plugging the replaced fan in other 3 pin socket just to check out the direction, it was the same; blowing inwards.

Is there any rule which direction CPU fans should blow? Maybe depends on type of used heatsink?

Can someone explain; thx?

 

[KGB1]

From my own experiences with the heatsinks and fans... SECC1/2.. Sockets...Slockets... It is essential that the Fan Blow Inwards towards the Heatsink. The Heat sink sucks up the heat...the fan Blows it away from the sides of the heatsink. That is the best way...I think heat issues were solved.. I tried reversing the procedure of the fan flow and usually its a few degrees higher but not too much that it worries me. So the conventional way is the best way.

 

[eplebnista]

The PII 400 does not create as much heat as most processors do now. I have a Dell XPS-R400(PII 400) that had no fan at all-just a larger heatsink and it ran fine for 2 years, then I upgraded to a PIII 850.

My $.02,
eplebnista

 

[lorlabnew]

Thx for response, guys.

I checked the other threads as well; and guess it could be used both ways, best is to try out where I'd get lower temperatures. Seems like for Intel CPU's this is not such an issue as for AMD processors.

Yeah, I'd love to remove the fan from my PII400 as well to make the PC more quiet (believe the large hs itself could be sufficient, but I can't since it won't even start without fan attached and running).