Bus Architectures for the A+ Certification Exams
Another term for the expansion slots on a computer’s motherboard is bus slots. A number of different bus architectures have been developed over time. For the A+ exams, you need to be able to identify the differences between each of these bus architectures and know which ones are more popular today.
|Architecture||Bus Width (In Bits)||Speed|
|VLB||32||Speed of local bus|
|AGP||32||66 MHz (1x), 133 MHz (2x), 266 MHz (4x), 533 MHz (8x)|
|PCMCIA (laptops)||16||33 MHz|
|PCIe||Serial||Uses multiple lanes, with each lane carrying 250 Mbps. As an example, a PCIe x1 slot can carry data at 250 Mbps, while a PCIe x4 slot can carry data at 1 Gbps. PCIe version 2 doubles those transfer rates.|