The Relationship Between
Overclocking and Cooling
This is
an article for overclockers which explores the age old question; "How does
cooling affect Overclocking?" In an enthusiasts attempt to reach higher clock
speeds, there will eventually come a time when the temperature of the
processor, memory, or some other electrical component becomes the limiting
factor. This is commonly known, of course, and is the prime reason why
enthusiasts rarely if ever overclock with the stock heatsink AMD or
Intel provide - it's simply not designed to handle the extra thermal load.
Luckily, overclocking has become so mainstream that
it has spawned an entire market to provide it with the necessary hardware.
For the average person
looking for a little more cooling action, the quick solution is to simply buy a more efficient heatsink,
and perhaps a higher CFM fan. Most of the time that is all that is that's
really required.
Yet, heatsinks are not the only method of coaxing a
toasty processor into giving up an extra GHz of speed. To deal with higher heat
loads, enthusiasts have been adopting watercooling systems like no tomorrow, or
simply building their own custom rigs from spare parts bought off Ebay, through
surplus stores, or even machined from solid blocks of metal in home workshops.
This has made watercooling more mainstream, and has resulted in more affordable
products for everyone. Bonus! The watercooling trend has also resulted in a lot
of cheaply made systems which are sold based on appearance, and not performance.
Sometimes used in
conjunction with watercooling systems are Thermal Electric Coolers (TEC), which are also known as "Pelt's" or "Peltier Coolers," so named for the inventor of the technology, Jean Charles Athanase Peltier. TECs can be a bit difficult to experiment with because of the high-current power supplies
typically required, and because they dump a lot of heat into the watercooling loop.
Thermoelectric cooling may sound pretty exotic, but what if you could
graft the essence of your refrigerator freezer on top of a CPU? Well, this is the same
idea that an enthusiast had at some point long ago, and this means of sub-ambient processor
cooling is called Phase Change Cooling (PCC). Phase Change Cooling adopts the same methods and equipment used to cool the standard kitchen fridge,
but modifies it to chill a specific point - most often a block of metal attached to
the processor - to very low temperatures of -60 degrees Celsius, or even colder.
The expense associated with
PCC systems has kept them out of the hands of most enthusiasts, but that hasn't
stopped people from finding other ways to cool their CPUs to well below Zero.
Dry Ice pellets, and even Liquid Nitrogen (LN2) have been used successfully in
extreme overclocking attempts - though at some point, electronic chips can
become too cold to function. Other factors like condensation can also wreak
havoc on electrical circuits.
Where
there are many documented instances of people using dry ice and LN2 to
cool their overclocked gear, we won't be discussing that today. It's just not practical,
no matter how cool it is. ;) Air, water, and phase change cooling can
be used 24/7, so we'll be focusing on those cooling methods as we examine what
role cooling plays in the overclockability of a processor.