All I wanted is a temporary hack of a serial mouse to see it a computer fan would work off a serial cable.
The RS-232 25 pin serial cable has pin9-10 an power. Research i learned Most mbds use SuperIO chips which are set to the RS232C standard i.e. +/- 12V with not a lot of current (usually 50 milliamps) available. so this is not a good idea i have found nothing to show fault protection unlike a USB prt that can be reset from the desktop.
Step 1: Parts Needed
2:P lll coppermine CPU fan (wow right beside the mouse how nice )
4:just a small phillips screwdriver
5:wire cutters (only to use on paper clip
Step 2: Open N Shut
Using a VDO meter find pin 2 and pin 3 between the plug and the header.
Then plug in the mouse and start computer.
warning!serial mouses not plug n play!
Do this only to an unplugged computer!
With the volt meter check that you have power at the mouse (mine were green / white wires yours might be different).
I used 2 short chunks of paper clip to plug the fan header to the serial header , if permanent then scrape back insulation and soder the leads from the fan to the wires.
Another paper clip to make a stand for the fan the legs are stuck into the 2 screw holes in the base.
Some reason I dont know why the fan will keep the serial mouse form booting on computer start up .
So if this is a permanent setup i would have to cut the "hot wire"and insert a micro switch.
Step 3: Running the Fan
At 50 milliamps the little fan is weak and not up to full speed so this is stupid. It does work .
The fan is 12VDC at .15 amps so it is at 1/3 power
My tower has a USB header on the MoBo and I have a Serial Jumper with same header have to try that ,might get more power form it.