Storage

Storage

What can we use to store data?
There are many different ways to store data. Some data storage methods can store more data then others, and some have faster access times. 

Hard Drive
One of the most used storage types today is hard drive storage, and it is clear to see why, as hard drives are

fairly cheap for the amount of storage you get on them, with 1TB hard drives being around £50. Despite the cheap price, the hard drive has many downsides. Hard drives commonly fail, and are also very fragile as they are as prone to static electricity as other parts in the PC. A typical lifespan of a hard drive wouldn't be more then a few years, and there could be serious faults that cause it's lifespan to decrease further. It's data access time is only slow as it has to physically move it's parts to access data. Despite this, the hard drive is an effective and cheap storage device and is used by millions every day.



SSD (Solid State Drive)
An SSD is like the hard drive, but much more expensive and reliable. An SSD costs more per MB, but with it you

are getting a storage device that rarely fails. It is much more reliable then a hard drive and has much faster data access time as there are no moving parts inside it. Solid state drives are commonly used in devices such as phones as they are portable and as such a storage device that can handle that movement must be used. If a hard drive was used, the movement may cause it to become faulty as it interferes with it's own movements.






USB And Flash Storage
Flash storage is similar to solid state storage except much smaller in size. This reduction in size allow the data

to be moved around and exchanged with other computers. Flash storage is typically used to move data between computers quickly and efficiently without the expensive price tag of the SSD.











Optical Drive
Optical drives such as CD's and DVD's are ideal for storing movies or songs or giving data to another person as 

they are very portable and durable. They are low cost although they are not very reliable, as if the disk does get damaged in a backup set of a program, the whole backup becomes unusable. The file size of CD's is also fairly small, while DVD's are slightly bigger.

Memory

Memory

What is the Function of Memory?

Memory has two major functions: To provide temporary memory (to store data from programs currently running) and to hold operating system applications that aren't temporary (a more longer term storage solution that is crucial for the computer to function). Both of these memory functions are stored in different places - the temporary storage solution would be stored in the RAM, while the longer term operating system applications would be stored on the hard drive. 

What is Volatile and Non-Volatile Memory?
Volatile memory is memory that can lose it's data when the power is lost. An example of volatile memory would be RAM, as when electricity is no longer supplied to it, it loses everything. As such, temporary program files are stored on the RAM, such as programs that are currently running. 
Non-volatile memory is a memory type that does not get deleted when power is lost. An example of this would be hard drive, as it stores the operating system. If this were volatile, the PC would no longer boot up as the core boot files would no longer exist. 

Different Memory Types
There are many different memory solutions to hold data:

RAM
Ram stands for 'Random Access Memory' and is used to store volatile data. It usually stores the data of the 

currently running program, and not anything important to the system, so that if power was lost, nothing is damaged. RAM can be read and written to depending on what the currently running program needs to do. 32 bit operating systems can only read up to 4GB of Ram. 64 bit operating systems running Windows 10 can read up to around 128GB, while other versions of Windows 10 such as Windows 10 Pro can read up to 2TB of Ram.




ROM
Rom stands for 'Read Only Memory' and as such can not be written to. An example of ROM would be the bios, 
as it can not be written to be any programs and comes with the motherboard. The reason ROM cannot be written to is because it stores the data that is necessary for the PC to boot up, at least into the BIOS where safe mode can be booted. If this was not read only, data may be stored in here that is not needed, and if corrupted, could also corrupt the BIOS which would jeopardize the whole system.







CACHE
The cache is found built into the CPU. It is like a mini RAM stick which reduces the access time of going to over

memory types such as the RAM, as it is built directly onto the CPU. It is fast, and has a small file size as they are expensive to produce. Different CPU's have different cache sizes, improving the overall access time of data. The cache is the fastest to access of all memory types.




RAM Types
Ram can come in many different types. There is the old type SDRAM (Synchronous Dynamic Random Access Memory), DDR SDRAM (Double Data Rate SDRAM), DDR2 SDRAM, DDR3 SDRAM, and DDR4 SDRAM is now available. The most commonly used today are DDR2, DDR3 and DDR4 as they are the most efficient. These different RAM types must match with the RAM types the motherboard supports, otherwise it will not detect and use the RAM. The higher the DDR, the higher the speed, so as such, DDR4 is currently the fastest speed of RAM,

Static and Dynamic Memory
Static memory is mainly used while a program boots, as it complies all the required data for the program to run correctly. Dynamic memory is memory allocated while the program is already running, and can be changed and modified in any way the program wants. 

Functions of a Processor

Functions of a Processor

What Does a Processor do?

The processor, or the CPU, is often referred to as the 'brain' of the computer. It makes up one of many processing units inside the computer, but is the most important of them all. The CPU performs calculations and runs programs for the user.

The CPU takes instructions from the RAM (Random Access Memory) and decodes the action before giving an output. CPU's are found in many devices other then PC's, such as tablets, smartphones and smart TV's. It is placed into the devices motherboard and interacts with other components to operate the computer.

As you can see on the left, the CPU is placed on the motherboard and is fastened in place so it does not fall out. A CPU cooler is usually placed on top to keep it cool so it doesn't overheat. Without one, the computer would not be able to function as it would get too hot.

The CPU's functions consists of three steps - fetch, decode and execute. It fetches the information, decodes it and then executes it. All of this is done very quickly, and only slows down when too much information is being requested.

Performance Features of a CPU

A CPU can be measured in many different ways. One of these is clock speed. To explain this clearly, we will use  

a CPU for sale on Amazon. 

This is the Intel i5, and the clock speed of the CPU is included in the title of the product - 3.40GHz. GHz are what we use to measure the clock speed, and shows how fast the CPU can fetch, decode and execute instructions given to it.

One of the other ways a CPU can be measured is the amount of cores it has. Again, we will use an example from Amazon. This AMD CPU has 4 cores, again, as shown in the title. This means that the CPU has four independent units that fetch, decode and execute. Each of these cores have the same clock speed.

Finally, another way a CPU can be measured is in the size of it's cache. The cache reduces the time the CPU access data, as it stores data in the cache to access it quickly. Here, we can see this AMD processor has a 2MB cache to store data, which is fairly small.

Makes of CPU's

There are three main CPU producers used today - Intel, AMD and ARM. Intel and AMD are commonly found in PC's, while ARM is less powerful and mainly found in smartphones. There are many differences between the three makes.

Intel

Intel are the most well known of the three. Intel offers a 'jack of all trades' CPU, in that it is good at a little of everything, and not specialized in anything specific. Intel processors have many different names such as the Intel Pentium, the i3, the i5 and the i7. For a general use PC, an Intel processor would be the way to go.

AMD

AMD are best for gaming. It has high clock speed to get the most out of playing games, and as such gets much hotter then any other processor. For anything other then gaming, the AMD struggles, as it isn't designed for 1080p video watching or music production, etc.

ARM

ARM are used mainly for smartphones and as such aren't as powerful. They are getting better as of late, and now come with multiple cores and higher clock speed to keep up with the fast processes of new phones.

Overclocking

Overclocking can be used to overwork the CPU and try to get more out of it. For example, if you had a 3.8GHz CPU and you wanted 4GHz, you could overclock the CPU at the cost of more heat to get more out of it. The CPU could overheat and it could damage it, reducing it's lifespan, but if you really need the extra power and have a good fan to keep the CPU cool, it could be worth it.

Heatsinks
Heatsinks are used to reduce the temperature of the CPU by applying a cool thermal paste to the top part of it. This cools the CPU down and reduces it's overall temperature, reducing the chance of overheating. Hearsinks work in combination with fans to cool the CPU down effectively.