Power Considerations
1. A multi-core processor runs faster than a single processor; as a result, it needs more electrical power. This additional power results in additional heat, which in turn increases the demand on the computer's cooling architecture. Another power consideration is the battery requirement for multi-core processor laptops. A multi-core laptop needs a more powerful battery to support the faster chip for a longer period of time.
Speed
2. A multi-core processor is not equal to the same count of separate processors. For example, a quad-core processor is not four times faster than a single processor. The actual speed of a multi-core processor falls somewhere between a single-core processor of the same type, and multiple processors equal to the core count. Exactly where the multi-core processor falls in this range depends on the speed of each core and the total number of cores.
Cost
3. Multi-core processors cost more than their single-core counterparts. However, because they share some hardware resources, multi-core processors tend to cost less than the combined cost of the same count of multiple processors.