The speed at which the processor communicates with the memory and other devices in the computer

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In a computer, clock speed refers to the number of pulses per second generated by an oscillator that sets the tempo for the processor. Clock speed is usually measured in MHz (megahertz, or millions of pulses per second) or GHz (gigahertz, or billions of pulses per second). Today's personal computers run at a clock speed in the hundreds of megahertz and some exceed one gigahertz. The clock speed is determined by a quartz-crystal circuit, similar to those used in radio communications equipment.

Computer clock speed has been roughly doubling every year. The Intel 8088, common in computers around the year 1980, ran at 4.77 MHz. The 1 GHz mark was passed in the year 2000.

Clock speed is one measure of computer "power," but it is not always directly proportional to the performance level. If you double the speed of the clock, leaving all other hardware unchanged, you will not necessarily double the processing speed. The type of microprocessor, the bus architecture, and the nature of the instruction set all make a difference. In some applications, the amount of random access memory (RAM) is important, too.

Some processors execute only one instruction per clock pulse. More advanced processors can perform more than one instruction per clock pulse. The latter type of processor will work faster at a given clock speed than the former type. Similarly, a computer with a 32-bit bus will work faster at a given clock speed than a computer with a 16-bit bus. For these reasons, there is no simplistic, universal relation among clock speed, "bus speed," and millions of instructions per second (MIPS).

Excessive clock speed can be detrimental to the operation of a computer. As the clock speed in a computer rises without upgrades in any of the other components, a point will be reached beyond which a further increase in frequency will render the processor unstable. Some computer users deliberately increase the clock speed, hoping this alone will result in a proportional improvement in performance, and are disappointed when things don't work out that way.

If data isn’t exactly the same as the original after compressing and decompressing, the compressionalgorithm is said to be __________. If data is the same as the original after compressing anddecompressing, the compression algorithm is said to be __________.

As Ebay wisely notes in its buying guide, “the CPU will limit how fast anything can occur in the system.” That’s an important fact to remember when choosing a processor for your computer. Although Central Processing Units play a major role in determining how fast computers, other factors also help shape your day-to-day work experience.

Processor Speed

1. A good way to understand how a processor works is to imagine that your job is to tell a thousand people how to do their jobs. The faster you can do that, the faster everyone works. Computer processors, or chips, operate in a similar fashion. A processor provides the instructions that multiple applications and processes need to perform their jobs. The faster it does that, the faster a computer operates. Faster computers often translate into increased productivity and efficiency. Computers onboard Apollo 11 in 1969 were less powerful than a cell phone. Today, technological advances in chip manufacturing make it possible for computers with faster processors to run programs, play movies and blaze through complex calculations at remarkable speeds.

Processors and Other Computer Components

1. Your processor also communicates with other computer components, such as memory and the hard drive. Because these components work together, a slow hard drive could make an application run slowly even if your computer has a very fast processor. Random Access Memory, or RAM, stores information that applications need. Windows and other applications move data into memory and read it back continuously. If your RAM reads and writes data slowly, that may also slow your computer down.

Clock Speed

1. It may be tempting to buy a processor because it advertises a fast clock speed. However, clock speed, as Computer Shopper notes, “is only marginally useful in gauging how ‘fast’ a CPU really is.” That’s because a chip’s architecture, cache and other factors also influence your computing speed. Clock speed refers to the number of cycles that a processor executes per second. A cycle is a unit of measurement during which a processor executes instructions. If you see a processor that has a rating of 3.1 GHz, it operates at 3.1 billion cycles per second.

Cores vs. Speed

1. A processor’s core count can be more important than its speed. You may have seen the terms dual-core or quad-core when reviewing processors. A dual-core chip consists of two processors while a quad-core chip contains four. You’ll find a quad-core chip useful if you like to run multiple applications at once or run programs designed to take advantage of four cores. Like their single-core counterparts, multi-core processors also perform faster when they have higher clock speeds.

Buying Tips

1. Whether you’re on a budget or you have extra money to spend, it’s important to shop for processors carefully. PCMag tells readers to purchase as much processing power as they can fit into their budgets because it’s not always easy to upgrade to a newer processor. Store technicians can offer purchasing advice if you visit electronic stores, while online review sites can help when you shop online. If you can visit a store, try out computers they have on display and see how fast they operate when you work with sample applications that you may use at work.

A computer's speed and processing power aren't attributable to a single component. It takes a number of pieces of hardware working together to determine your computer's overall performance. The key is how well, and how quickly, all the important components communicate with each other to perform actions.

The central processing unit (CPU) is effectively your computer's brain. This chip executes all processes and instructions in your computer, responding with the appropriate action depending on what order you give it, such as opening a program.

The speed of your CPU, known as clock speed, is the number of cycles the chip performs in one second. The faster the CPU runs, the more processes it can run at any given time. A CPU with a clock speed of 3 GHz, for example, can run 3 thousand million cycles each second.

The processor's cache is the onboard memory, used to store information so the processor can access it quickly. The more cache your CPU has, the more data it can store and the faster it can run processes.

Also known as the system bus, the front side bus is what connects the CPU to the rest of the components attached to the motherboard. Measured in MHz or GHz, the speed of the front side bus determines how quickly the CPU can communicate with the graphics card, RAM and other components.

The bus speed is usually a ratio of the CPU's speed; the smaller the ratio, the the more efficient the processor. For example, a 2.4-GHz CPU with a 400-MHz bus is a 6:1 ratio. This setup would work more slowly than a 2-GHz CPU and 1-GHz bus, which is a 2:1 ratio.

Random access memory, or RAM, is the temporary holding spot for data. When running processes, your CPU looks first at its onboard cache for data, then to the system's RAM. The more RAM you have and the faster it can transfer information, the more data your CPU can access and use before having to jump to the much slower hard drive for data storage.

RAM specs are listed in terms such as DDR3-1600. The number after the dash refers to the number of transfers the chip can handle. The higher the number, the faster the memory is, and the more memory you have installed, the more transfers it can handle.

After the CPU's cache and system RAM, the hard drive is the third storage space your processor accesses for data. Simply put, the bigger and faster the drive, the better your computer's performance. A well-organized drive, with plenty of empty space and no heavy fragmenting, will help the read/write head find the requested information faster.

Hard drives are measured in rotations per minute, or RPM, which essentially means how fast they spin to allow the read/write head to find the requested data. So a hard drive with 200GB of empty space with a speed of 7200RPM would theoretically find data faster than a drive with only 20GB of space running at 5400RPM. The more cluttered the drive, the longer it will take the read/write head to find the data it's looking for.