CPU is also known as, the processor. As the name implies, it processes the instructions given to it. If something needs to be done, it is sent to the CPU (Central Processing Unit). CPU executes/processes computer programs. It interprets and responds to the commands accordingly. It is often referred as, the Brain of the computer. Lately, they are also termed as Integrated Chips. If there lies no CPU then there exists no computer.
There has been a great evolution since its invention. The size, form, design, speed etc has changed dramatically as and when the requirements and demand changed. The latest or modern CPU’s are Integrated Circuits (ICs), having a size of less than four centimeters square. Because of its small size, it is also termed as Microprocessor.
Many components like one or more execution core, registers, cache (memory), Arithmetic Logic Unit (ALU), input and output bus controllers etc., are integrated on a single chip. Some of the companies like IBM, Intel, AMD, Motorola, Sun, Texas Instruments etc., make CPUs. These companies make CPUs for higher and lower end computers like Super Computers, Mainframe computers and microcomputers, respectively. Snapdragon, ARM Cortex, Nvidia Tegra, are some common names when it comes to mobile phone CPUs.
Arithmetic Logic Unit (ALU) performs arithmetic and logical operations. Control Unit (CU) extracts instructions from the memory. It decodes the instructions and executes using ALUs when necessary. Registers are used for temporary values during computation. The data which is needed in memory, for the CPU to process is obtained by sending its address through address bus, the data bus retrieves the data found at that address and is sent to memory. Cache is a smaller and faster memory. It stores the most frequently used data. It readily decreases the average time to access memory. It avoids reading or writing of frequently used data every time from main memory. Sometimes, data in the queue waiting to get processed is also stored in this cache memory.
The processor can be described in many ways based on the number of bits it processes per instruction, number of clock cycles and number of execution cores.
Processors have evolved dramatically and modern processors have up to 7 cores. Intel® Core™ i7-3930K Processor (12M Cache, up to 3.80 GHz) and Intel’s Core i7-620M with a processor speed of 2.66 GHz and maximum over clock speed of 3.33 GHz and AMD Phenom II X4 with a speed of 3.4 Ghz are some of the latest processors.
Processing speed of Super computers can be up to 2.5 petaflops (2.5 thousand trillion calculations per second). FLOPS is Floating Point Operations per Second, it is a measure of computers performance.
CPU temperature is kept under control to prevent the over-heating of CPU and ultimately being burnt by using additional fans, keeping the temperature of the room low, using a case, which has sufficient air flow around the CPU, cleaning dust, using coolers, etc. Thermo electric cooling and phase change cooling are also used to cut down the temperature of the CPU. However, the processors made these days are of very high speeds but are controlled, using the above methods.
Deleted file recovery from a laptop hard drive
Computers are used by employees at offices, home users etc, but laptops are portable which can be used anywhere we want to work. Laptop hard drive stores large amount of data like documents, pictures, music, video etc, which are not safe due to several reasons. One among them is virus attack, by which files stored in hard drive are corrupted / deleted / lost. To recover deleted files from laptop hard drive you can make use of Remo Recover.