2. Index Goes Here

3. Slide 1: The Chemistry of Cooling a PC Computer Processors (CPUs) generate heat Transistors are semi- conductors contained within the CPU core Resistance creates Heat Moore’s Law dictates that transistor count in CPUS will double every couple of years. Generally Speaking: More transistors = More Heat The Chemistry of Cooling a PC

4. Slide 2: The Chemistry of Cooling a PC Heat creates “Electro- migration” which destroys sensitive circuits. Heatsinks are used to dissipate the heat from computer CPUs Performance has changed dramatically over the years

5. Slide 3: The Chemistry of Cooling a PC Heatsink design has gone from simple passive aluminium to actively cooled copper or aluminium/copper hybrid. However, Aluminium is 1/3rd of the weight so Per unit volume, Copper can absorb more heat. But: Aluminium looses heat faster then Copper. = Good Hybrid Heatsinks. Why? Heat Conduction of Copper = 380J s -1 m -1 K -1 Heat Conduction of Aluminium = 200J s -1 m -1 K -1 Specific Heat Capacity of Copper = 0.902J g -1 K -1 Specific Heat Capacity of Aluminium = 0.385J g -1 K -1

6. Slide 4: Water cooling: From Enthusiast to Mainstream Greater cooling potential, less noise, less stress on the system. Why? Specific Heat Capacity of Water = 4.179J g -1 K -1 Specific Heat Capacity of Air (1atm) = 1.01J g -1 K -1  Water cooling: From Enthusiast to Mainstream

7. Slide 5: Water cooling: From Enthusiast to Mainstream However, problems with the water system now occur. Problems with water systems: Water and Electricity = Bad >1 metal systems creates an electrochemical cell = erosion of water blocks. All Copper systems are now primarily used.

8. Slide 6: Water cooling: From Enthusiast to Mainstream Many argue the water system should use distilled or deionised water. Deionised water Advantages: Removal of reactive ions. Disadvantages: Still solvated solids remain Distilled Water (Boiled Water) Advantages: Pure water – nothing else solvated Disadvantages: A “void” in the water causes ions from the Copper blocks to restore ionic equilibrium

9. Slide 7: Water cooling: From Enthusiast to Mainstream What can be done about it? Possibly use a Copper solution in distilled water Common Ion Effect inhibits further ionisation. Possible solutions: Copper Hydroxide Copper Nitrate Copper Carbonate Copper Oxide Problems Lower heat capacity. Possible crystal growth if flow is slow. Chemically “active” Copper solutions. How soluble are they?

10. Slide 8: Water cooling: From Enthusiast to Mainstream What can be done about it? Use a completely different liquid like PFC’s (Per-fluoro-carbons) C 6 F 14 : Bpt: 56ºC Non toxic, non corrosive, non electrically conducting. Problems with PFCs Lower heat capacity If the pump fails – PFC boils Expensive and possible restricted use.

11. Slide 9: Summary Summary Type summary in here

12. Slide 10: Acknowledgments University of Alaska Physics Dept. University of Indiana Northwest CSL Metallurgical and Materials Engineering Department Bit Technologies Wizard Designs Pro Cooling Thank you for your attention! Acknowledgments