upgraded from dual to quad core, cpu is cooking

[rommie]

Replaced a core 2 duo e5400 with a q6600, on a machine that doesn't see very much usage at load. I'm not too confident with replacing cpu's so I took it to a friends' place, the dual was running at 55c idle before I packed it up (hot day). I noticed that my friend replaced the stock fan with one that seemed to be turning really slowly, he said that's normal and it will speed up when under load. The cpu at his place reached 50c as soon as we turned it on.

Anyway, I got home and noticed that the idling speed for the cpu fan is only 800rpm... it's IDLING at 65c. I just did a prime95 test and the fan speed went up to 4000 rpm, but not before the cpu hit 85c (!!!) - now it's idling at 69. I suspect the fan, but could it be because I'm using a stock dual core fan on a quad? I've never even heard the stock fan spin up when running the dual core at load.

 

[wagex]

go into the bios and look at the "q fan" setting or the "health" section of the bios it will let you adjust the fan speed to a constant or adjust the ammount the fan speeds up depending on the temp.

 

[rommie]

go into the bios and look at the "q fan" setting or the "health" section of the bios it will let you adjust the fan speed to a constant or adjust the ammount the fan speeds up depending on the temp.

I did look for that, it's a motherboard in a proprietary case, absolutely nothing you can do about the cpu or fans apart from turn cores off and disable cache. Not even a temperature monitor!

 

[wagex]

well only other option would be to swap out the cooler for one with a fan with higher rpm duty cycle or a 3 pin fan, or plug the cpu fan into a 3 pin header. if theres not one clip the blue wire to disable the pwm control. beware it will run at 4k rpm or what ever the max fan speed it.

 

[rommie]

well only other option would be to swap out the cooler for one with a fan with higher rpm duty cycle or a 3 pin fan, or plug the cpu fan into a 3 pin header. if theres not one clip the blue wire to disable the pwm control. beware it will run at 4k rpm or what ever the max fan speed it.

Plugging it into a 3 pin header worked fine thanks, temps are 10-15 degrees lower. Just curious though, what did that actually do - the fan is running at 2000 rpm, but what's causing it to go at that speed compared to, say its' minimum or maximum?

 

[wagex]

thats weird
it should be running its maximum speed since it has no pwm signal. maybe it has some circuitry to just default to 2k when its loses pwm.

 

[rommie]

thats weird
it should be running its maximum speed since it has no pwm signal. maybe it has some circuitry to just default to 2k when its loses pwm.

Maybe it matters which three pins are plugged in? I did that instead of cutting one of the wires.

 

[wagex]

its the same thing as cutting the wire.