Fan speed question

[Raphael Argus]

Hello All, I just picked up a fan to use in an older PC. The system was running a little warm and did not have any fan in it. I set it to exhaust and it seems to be running VERY slow, in the BIOS it even shows the fan speed in RED. CPU fan is around 3500rpm and this one shows as 1500rpm or less. I popped it in another PC and it seemed to run faster and better. Any ideas? Thinking maybe it's a power supply issue, the 5v shows to be running at under 5v's. Any help is appreciated.

 

[Static_11]

what psu you have?

 

[FlashDude]

If it is a 120mm fan then that speed is fine, If it is 80mm then its to slow, try plugging it in directly to the psu not the motherboard. and don't be concerend with the 5v case fan's are 12v.

 

[Raphael Argus]

It's a 450Watt PSU, an offbrand. Probably a hunk of junk. I'll see if I can find an adapter to plug it into one of the molex plugs. The PSU doesn't have any of the 3-prong fan connectors. Thanks for the help

80mm fan

 

[FlashDude]

If it is a 120mm fan then that speed is fine, If it is 80mm then its to slow, try plugging it in directly to the psu not the motherboard. and don't be concerend with the 5v case fan's are 12v.

Is it a 120mm fan???

 

[magouster]

It's a 450Watt PSU, an offbrand. Probably a hunk of junk. I'll see if I can find an adapter to plug it into one of the molex plugs. The PSU doesn't have any of the 3-prong fan connectors. Thanks for the help

80mm fan

Flashdude, he says it is a 80mm fan