1. 外围组件互连(PCI)：
PCI 是一种计算机总线，用于连接计算机系统中的硬件设备。常规 PCI 是 PCI 的另一个名称。 PCI 被设计为并行总线并具有分配时间量的单个总线时钟。 PCI 于 1992 年由 Intel 推出。 PCI 总线的标准宽度是 32 位或 64 位。热插拔是 PCI 中的一项可选功能。
2. 外围组件互连 Express (PCI-e)：
PCI-e 是 2003 年推出的外围组件互连的替代版本。虽然热插拔功能在 PCI 中是可选的，但新版本具有热插拔功能。 PCI express 是连接显卡、Wifi、硬盘和其他硬件设备的串行总线。它的工作速度比 PCI 快，输入和输出引脚数更少，使其比 PCI 工作得更好。
PCI 和 PCI express 的区别：
| S.NO | PCI | PCI express |
|---|---|---|
| 1. | PCI is a computer bus that connects hardware devices. | An advanced version of PCI bus that connects graphic ports, Wifi and other devices. |
| 2. | It was introduced in the year 1992 by Intel. | It was introduced in the year 2003 by Intel, Dell and other organizations. |
| 3. | It is a parallel bus interface | It is a serial bus interface. |
| 4. | Conventional PCI is the other name for PCI. | PCI-e is the abbreviated name for PCI Express. |
| 5. | It works slower. | It works faster. |
| 6. | PCI provides a slower data rate | PCI Express provides faster data rate. |
| 7. | The PCI slots are standardized | The PCI-e slots depends upon number of lanes. |
| 8. | The speed of a PCI slot is upto 133MB/s. | The speed of a PCI-e slot is upto 16 GB/s. |
| 9. | It has less features. | It has more features. |
| 10. | It may or may not have hot swapping feature. | It has the hot swapping feature. |