A multi-core CPU is a computer processor which has two or more sections. Each section of the chip executes instructions as if it was a separate computer. The actual processors are still on one chip. On this chip every core looks mostly like the other. They are several mostly independent cores which work together in parallel. A dual-core processor is a multi-core processor with two independent microprocessors. A quad-core processor is a multi-core processor with four independent microprocessors. As you might be able to tell from the prefix, the name of the processor is based on the number of the microprocessors on the chip.
Until 2005 single-core processors outnumbered multi-core processors.[source?] In the years before there were only multi-core solutions used in individual cases. The usual way to make a computer faster was to increase the clock rate. But at a frequency about 4 GHz the CPU would get too hot and take a lot of electricity. This was the point when multi-core processors became more important. Therefore, the demand for multi-core processors increased. In the second half of 2006 the best processors were dual-core processors. Since 2006 the development has gone on, so that the new processors get four or more independent microprocessors. Today, single-core processors are not used in new personal computers, but they remain popular in embedded systems.
- Having a multi-core processor in a computer means that it will work faster for certain programs.
- The computer may not get as hot when it is turned on.
- The computer needs less power because it can turn off some sections if they aren´t needed.
- More features can be added to the computer.
- The signals between different CPUs travel shorter distances, therefore they degrade less.
- They do not work at twice the speed as a normal processor. They get only 60-80% more speed.
- The speed that the computer works at depends on what the user is doing with it.
- They cost more than single core processors.
- They are more difficult to manage thermally than lower-density single-core processors.
- Not all operating systems support more than one core.
- Operating systems compiled for a multi-core processor will run slightly slower on a single-core processor.
Operating System Support
The following operating systems support multi-core processors
In the next years the trend will go to multi-core processors more and more. The main reason is that they are faster than single-core processors and they can be still improved. But in the future there will be still some applications for single-core processors because not every system needs a fast processor.