The processor is the brain of your computer. Its speed and build can dramatically impact the speed of your computer. When looking for an upgrade to your computer, understanding what a quad-core processor is and how it works helps ensure that you choose the right upgrade. Before settling on any processor, look at third-party benchmarks for that processor to see the real-world performance speeds.
Understanding the Hardware
A quad-core processor is exactly what it sounds like: a processor with four cores. This is multi-core processor technology built on dual-core technology, which includes two processors on one physical circuit. A quad-core CPU has two connected dual-core chips. In this setup, each set of cores has a shared cache. When the two halves of the quad-core processor must communicate they do so externally via the frontside bus. Before you fit a quad-core processor into your computer, you must first check that your motherboard supports the hardware.
Gigahertz and Cache
The point of choosing a quad-core processor is speed. However, not all quad-cores are created equal, and some are significantly faster than others. Two factors to consider when looking at processors in the same family is the clock speed (typically measured in gigahertz) and cache (typically measured in megabytes). The GHz refers to how much it can process each second. A 2.6 GHz processor, for instance, can go through 2,600,000,000 cycles per second. The cache refers to memory on the processing unit; the computer uses this memory to store things you frequently access. A higher cache can store more items. This improves the overall speed, as it is much faster for the processor to pull from the cache than from the computer's memory.
Not every program is made to benefit from the speed gains in a multi-core processor; many are written with single- and dual-core chips in mind. If you only use your computer for casual Internet browsing or office software, then a quad-core CPU is not going to drastically improve performance over a dual-core one. If you deal with a lot of high-definition media content, then a quad-core processor does have benefit. Quad-core processors are a boon for users who run intensive 3D graphics, editing, or scientific/mathematic programs.
Other Factors in Computer Speed
While a quad-core processor is significantly faster than its single-core ancestors, this does not mean that your computer will speed up just from the addition of a better processor. Other computer components such as your hard drive play a huge factor in computer speed, as every program you use and file you access must be read from and written by the hard drive. Users improve this spec by upgrading to a solid state drive, which removes the slowdown from moving parts within the hard drive. The amount of RAM also has a huge impact on your ability to multitask while using a computer.