Which is Faster PCI or PCI Express
Compare PCI vs PCI Express
The slots shown here represent the slots on a computer motherboard that a video card would be mounted into. To compare, PCI Express is a serial based technology, data can be sent over the bus in two directions at once.
Bandwidth Table
PCI | 1056 Mbps |
AGP 8x | 2.1 Gbps |
PCI Express 1.0 | 12 Gbps |
PCI Express 2.0 / x16 | 16 Gbps |
PCI Express 2.0 / x8 | 8 Gbps |
PCI Express 2.0 / x4 | 4 Gbps |
PCI Express 3.0 / x16 | 32 Gbps |
PCI Express 3.0 / x8 | 16 Gbps |
PCI Express 3.0 / x4 | 8 Gbps |
PCI Express 3.0 / x1 | 2 Gbps |
IDE (ATA 100) | 800 Mbps |
IDE (ATA 133) | 1064 Mbps |
SATA | 1.5 Gbps |
SATA III | 3 Gbps |
SATA 6 | 6 Gbps |
Firewire | 400 Mbps |
USB 1.0 | 12 Mbps |
USB 2.0 | 480 Mbps |
USB 3.0 | 4.8 Gbps |
USB 3.1 | 10 Gbps |
DisplayPort 1.1 | 10.8 Gbps |
DisplayPort 1.2 | 21.6 Gbps |
DisplayPort 1.3 / 1.4 | 32.4 Gbps |
Gigabit Ethernet | 1 Gbps |
What is the difference in PCI vs PCI Express
Normal PCI is Parallel, and as such all data goes in one direction. Hence PCI Express will provide much faster video than the older PCI. (See more port types at the bottom of this page).
Each 1x lane in PCI Express can transmit in both directions at once. Also please note that in PCI Express bandwidth is not shared the same way as in PCI, so there is less congestion on the bus.
The “x” in an “x16” connection is typically represented as “by” (by 1 [x1] , by 16 [x16] etc). PCIe connections are scalable by one, by two, by four, and so on.
PCI Express Connections
Each lane of a PCI Express connection contains two pairs of wires — one to send and one to receive. Packets of data move across the lane at a rate of one bit per cycle.
A x1 connection, the smallest PCIe connection, has one lane made up of four wires. It carries one bit per cycle in each direction. A x4 link transmits four lanes etc.
What is PCI?
PCI is short for Peripheral Component Interconnect. The PCI slot is a local system bus standard that was introduced by the Intel Corporation, however, it is not exclusive to any form of processors and PCI slots are found in both Windows PCs and Macs. PCI slots allow numerous different types of expansion cards to be connected inside a computer to extend the computers functionality. Examples of PCI expansion cards are network cards, graphics cards and sound cards.
Although the bus speed is slightly slower than PCI Express, the PCI slots are the most common type of slot and found on most motherboards today. If you are installing a new video card and you are unsure about the slots, stick with the PCI version of this card it will always work.
Computer PCI and PCI Express (PCIe)
The 32-bit PCI bus has a maximum speed of 33 MHz, which allows a maximum of 133 MB of data to pass through the bus per second. Different PCI Express specifications allow different rates of data transfer, anywhere from 400 MB to 8000 MB of data per second and beyond. (see table at top of page).
SUMMARY
Since PCI, PCI-X and PCI Express are all compatible, all three can coexist if the operating system allows it. As of 2011, the PCIe format is the most common type of video adapters by far and now considered the standard. Network and sound adapters, as well as other peripherals, have been slower in development to adapt to PCI Express but it is coming. Since PCIe is compatible with current operating systems and can provide faster speeds, it will eventually replace PCI as a PC standard. Gradually, PCI-based cards will become obsolete.