Compaq Evo W8000 Hardware Reference Manual page 59

Hardware Upgrades
Guidelines for Separating the Heatsink/Processor Assembly
2-44
Before upgrading your workstation with a new processor, the
following sequential events must take place in order to remove the
existing heatsink and processor assembly:
1. The heatsink and processor assembly need to be heated to an
optimum temperature to break the compound bonding them
together. See the following sections:
"Heatsink Cool-Down Time"
"Heatsink Warm-Up Time"
2. The heatsink must be separated from the processor.
3. The processor must be released from the processor socket.
Heatsink Cool-Down Time
The heat generated from the processor core transfers to the heatsink
making the assembly too hot to handle. From a power-on state to a
power-off state, it takes 13 minutes to cool the heatsink sufficiently
so that it can be handled comfortably while the compound holding it
to the processor remains pliable.
Compaq Evo Workstation W8000 Hardware Reference Guide