November 28th, 2004, 09:43 AM
CPU fan Mod
Hi guys I have a MSI Mother Boad which has a function of controling all
system fans according to system load(fans will spin faster when in
heavy cpu usage and slower when in idle state).
I bought Cooler Master's JET 7, for my processor as the default AMD
fan was not doing its job that well(processor can reach up to 70
degrees at times).
The problem now is, the cooler master's jet7 comes with 2 connectors.
One four pin connector like the power connector for harddisk and stuff
to power it but only two wires are connected (black GND, Red
+voltage)and a 3 pin connector with only one wire, which is for fan
My mother board can only control the speed of the fan if the power
cable is fixed to the 3 pin connector as well(as the voltage given to
the fan is controled by the mother board in the 3 pin connector) And
should not be drawing fixed voltage directly from the 4 pin connector
from the powersupply.
I want to cut the 2 wires from the 4 pin connector(black GND, red
+Voltage) and connect to the 3 pin connector solving the problem. Now I
know which wire goes where and how to do it and stuff but all i'm not
sure is, is it ok to connect the fan's power wires which from the fan's
data sheet claims to be 13.8V at max speed be connected to the 3 pin
connector,which I know from the mother boad's user guide which says
supports fans with 12V.
Any possibility it may cause any trip and damage my system since the
fan CAN draw more then 12V at MAX speed?
Link to the fan's website below:
December 1st, 2004, 10:13 PM
Dont worry about letting the motherboard control the fan speed. just connect the 3 pin plug with only the yellow wire to the board so that it know that there its a fan running and connect the other one to the 4 pin connector. myself i dont like for the board to control the fan. id rather let it run full speed all the time. but if you want your should be able to cut the wires and do it the way you want it wont hurt anything but if i was you i wouldn't
December 8th, 2004, 08:40 AM
If you are not shy of soldering I built the following for my systems and it works great. Using in two system, overclocked athlon palomino and dual overclocked celeron.
Only side affect is cannot use fans on this with fan monitoring on motherboard. I do not set CPU/Chipset fans to spin down, just case fans, so not a great loss for me. You can use on chipset/cpu fans but cannot use with monitoring lead on motherboard (no great loss, as temperature is more critical to watch than the actual fan speeds, unless case gets dirty and high probability of fans clogging).
Cheap to make, works great, and is adjustable. It is capable of taking a huge load (more fans than a typical PC would fit).
Does not answer your question but may eliminate the need for the question. I prefer to attach as few fans to motherboard as possible (especially high watt/mA fans) so this would be my recommendation.
If you make the circuit I pointed out, I tore apart old power supplies to get heat-sinks for the MOSFETs and the rest of the components are fairly easy to get (radio shack, etc.).