COMPTIA A+ Practice Exam

In what units is system bus speed measured?

1. Bits per second

2. Hertz

3. Clock cycles, MHz

4. Watts

The correct answer is: Clock cycles, MHz

The system bus speed is measured in hertz (Hz), which reflects the number of cycles per second of the bus. As such, the correct answer addresses how the frequency of the bus's operation is quantified, typically expressed in megahertz (MHz) or gigahertz (GHz) for contemporary systems. This measurement indicates how many cycles the bus can carry out in one second, thereby providing a direct correlation to the speed at which data can be transmitted across the bus. This is crucial for understanding system performance, as a higher bus speed allows for quicker data transfers between the CPU, memory, and other components, improving overall system efficiency. Other options, such as bits per second, while related to data transfer rates, focus more on bandwidth rather than the frequency of the bus itself, and watts pertain to power consumption rather than speed.