Processors

Sources: I7:http://download.intel.com/pressroom/kits/corei7/images/Intel_Core_i7_right_side.jpg,
 RYZEN: http://s3.amazonaws.com/digitaltrends-uploads-prod/2016/12/AMD-Ryzen_004.jpg

Clock Speed

The processor (also known as the central processing unit [CPU]) is one of the most vital parts of any computer. It dictates the speed in which data can be read/written from and to memory as well as how quickly a computer can perform basic arithmetic and logical operations. In essence,  the faster your processor, the faster your computer executes tasks.

Presently, most processors are multi-core processors unsurprisingly comprised of multiple cores within a single chip. A core is another name for processor embedded in parallel with other processors. The use of multiple processors within a single chip makes it easier for a computer to carry out a higher volume of tasks at a faster rate since the work load is split across each core within the processor. Typically, processors are marketed and measured by the speed they can carry out instructions. This speed is called the clock speed and it is governed by how quickly a processor pulses electric signals.

Within each core of a processor, there exists an intricate oscillator circuit that converts DC current from a power supply to an AC signal. The frequency of this signal is dependent on the resonant frequency properties in materials used to create the processor. When the resonance frequency of a material is reached, the system oscillates with a much greater amplitude. In terms of processors, this means that if the material used to drive the frequency in the circuit is kept at its resonance frequency, the processor can supply a maximum amount of energy at a given rate. Any frequency too far below or above the resonance frequency will result in a smaller amplitude and therefore less energy.

In older models of processors, the resonant properties of quartz crystals were used to control the frequency at which AC signals could be generated. These processors ran each core at roughly 1MHz or 1,000,000Hz. Today, processors are much faster and are now measured in terms of GHz (1,000,000,000Hz).

Data Transfer

We now know how quickly processors can carry out instructions but how are these instructions actually transferred on a micro-physical level? It turns out that processors are made up of multiple circuits each of which is composed of roughly 55+ million transistors. These transistors are inherently small and can be thought of as the pipes that carry data to and from the processor. In the middle of each of these pipes is a 'valve' that allows data to be blocked from entering or leaving the pipe. When a potential is applied to the valve, an electric field is created that allows the data (charged particles) to flow in or out of the pipe. When the potential is removed the electric field is removed and the data stops flowing. This type of data transfer is nearly identical to charges flowing in a wire when a light switch completes a circuit. A force from the electric field moves a huge number of charged particles at a slow drift velocity to the light. Similarly, the electric field through the transistor causes data to move to or from the processor depending on the direction of the electric field force.

Heat

Previously, we talked about charged particles and their drift velocity. The drift velocity is the average velocity a charged particle travels as it ricochets off of other moving particles while moving through a conductive material. Since these materials are not superconductors, charged particles experience a resistance as they flow to and from the processor. This resistance converts the electrical energy of the charged particles into heat energy. Judging by the fact there are 55+ million transistors in a single circuit of a core in a processor with multiple cores, this heat energy adds up fast. Without cooling the processor with something called a heat-sink, the thermal energy excites the particles within each transistor, causing them to oscillate faster. With this increase in oscillation, the flowing charged particles have a higher collision rate and therefore have a slower drift velocity resulting in slower data transfer.

By utilizing a heat-sink, computers can regulate the temperature of a processor and optimize the rate of data transfer to and from the processor. The heat-sink is designed to take up the largest amount of surface area on a processor to guarantee even cooling distribution and faster heat transfer. Heat-sinks are usually made of high heat capacity metals and are cooled as they gain heat from the processor by a fan. Between the processor and the heat-sink is a layer of thermal paste that seals the connection and removes any air gaps between the two components. As the processor heats up, because the heat-sink is in direct contact with the thermal paste which is in direct contact with the processor, heat is transferred to the heat sink by conduction. This transfer continues until the two components are in thermal equilibrium, but because the heat sink is cooled with a fan and different processes heat up processors to variable temperatures, heat is constantly being transferred and regulated.  Nevertheless, the dynamic nature of heat-sink cooling via conduction protects the processor from overheating and losing data transfer speed.