The heatsink goes on the Northbridge Chipset.
Without it the chipset over heats.
If one of the little U's came off of the motherboard you need to find it & remove it from the case so it doesn't short anything out.
The easiest way to fix it is with double sided thermal tape ,http://cgi.ebay.com/Sekisui-5760-Dbl-Sided...id=p3286.c0.m14
Unplug the computer
Wait a minute & clean the chipset with a piece of paper towel & rubbing alcohol
Clean the heat sink also
Cut a piece of the tape to just fit the heatsink
Put it on the heatink & then stick the heatsink on the chipset.
Just let the wire part just hang out, don't try using it !
Provided the chipset wasn't damaged it's good to go.
I keep a supply of the double sided thermal tape for just such repairs.
It also works on video card coolers as long as they aren't real heavy !
NEVER use thermal tape to on a CPU heatsink !
The other way of fixing it is to try & epoxy the U back on.
Messy & usually doesn;t work out well .
Edited by fairjoeblue, 01 August 2009 - 04:25 PM.
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