How to Re-use Thermal Paste/Grease in CPU Heatsink

It so happened that I had to attach a secondary hard disk inside my Windows PC. All I had to was attach the SATA cable and power cable to the hard disk and it should have been done. But one slip of hand while doing so resulted in pulling up the lever that holds the CPU heat sink in place. The heat sink instantly became loose and now I had another problem at hand – apply the new thermal compound to the CPU heat sink. Usually it is not problem and applying the thermal compound is very easy in itself, but at midnight no computer stores in my area are open that keep any type of thermal compounds to be used with electronic chips or CPU heat sinks.

I really had to finish my project work using this computer, so I asked my friends for a workaround. One of my room-mates suggested that I can use a mixture of white toothpaste and Vaseline petroleum jelly in place of the thermal paste. But the idea seemed ridiculous to me and I passed on it. One of my other friends suggested that I could re-use the existing thermal paste by mixing it with some alcohol. This seemed like a good idea to me at the time. I gave it a try and it made the CPU work through the night. Here is the temporary way of re-using the old thermal paste:

  1. Assuming that you are in a situation like mine and have already removed the heat-sink assembly from the top of the CPU chip, do not clean off the thermal compound from either the heat-sink or the CPU.
  2. Dab a tiny cotton-ball in anhydrous alcohol (rubbing alcohol of strength around 70-90%) and sprinkle some drops of the alcohol on the old thermal paste both on the heat-sink and the CPU. Do not drop too much rubbing alcohol, just enough to make the thermal paste a little wet.Reuse Thermal Compound
  3. Place the heat-sink back on the CPU and use the lever or the screws to fix it back on. Now you are back in business – you can use your PC once again.

Remember this is only a temporary fix for situations when you cannot buy or do not have access to new thermal paste. Thermal paste is cheap and is available easily on many online stores like Amazon. So replace the old thermal paste with the new one as soon as possible. And in the meanwhile, keep an eye on the CPU temperature using  a program like Hardware Monitor.