Peripheral Component Interconnect Express (PCI Express or PCIe) is an expansion card for computer systems which has the purpose of providing a high speed serial bus that descends from the old parallel PCI buses that computer systems had before then. The immense jump in bandwidth spawned a new era in computing.
Which One Is Better?
It is important to bear in mind that PCIe slots are each designed with a particular type of device in mind, making none better than the other. It is obvious that x16 PCIe slots are much more capable of transferring larger volumes of data than x1 PCIe slots every second. This is why PCIe x16 became ideal for graphics interfaces, which hunger for the heavy bandwidth capacity of a 16-lane PCI slot.
What Connects to PCIe X1 Slots?
There are a number of devices that connect to the single-lane PCIe slots on a motherboard, including network cards, audio cards and debug cards. The reason PCIe x1 is favoured for these devices is because they do not require the massive bandwidth brought about by slots with extra lanes. As a result, 250MB/s was enough for these devices, and they were created to be connected to PCIe x1 interfaces. Some higher-performing versions of these devices, like 1-Gbit network cards and very high performing audio cards for studio use, will probably need an extra lane.
Main Differences Between X1 and X16
The single-lane and 16-lane PCIe slots on a motherboard undoubtedly have vast amounts of similarities. However, there are things that set them apart. For example, PCIe X16 benefits from 16 times the power of X1. The reason for this is the higher amount of lanes, which will be more capable of directing large volumes of data, much like more lanes on a road can direct higher volumes of vehicles.
Why Aren't They All the Same?
The reason X1, X4 and X8 were created was to reduce manufacturing costs (as well as retail prices) of all the cards that were created. A sound card, for example, does not need 4 to 16GB (depending on the version of PCIe used) of data bandwidth. Building a PCIe X16 sound card would be a waste of capital and power. More electricity is required to run the extra lanes on the PCIe bus, and you will end up consuming unnecessarily on a card that can settle for a mere 250-megabytes per second of bandwidth. Unlike PCI, the PCIe concept incorporates different slots for different types of functions, all using the same guidelines and incorporating new lanes if more bandwidth is required.
More Interesting Facts About PCI Express
You will be amazed to know that you can actually connect a PCIe card to a slot with at least the same number of lanes in it. In other words, a PCIe X1 card can go into an X4, X8 or X16 slot. The only drawback is that the process does not work reciprocally (for example, you cannot connect a PCIe X16 card to an X1 slot) because of physical limitations. When you connect a card to a PCIe slot, it only uses the amount of lanes that the card asks for.
- Jona:Wikimedia Commons