Understanding all the PCIe slot and their configuration can get a bit confusing especially when you are trying to install newer devices.
The short answer to the question: which PCIe slot for wireless card is most suitable is: the PCIe X1 slot. In other words, the PCIe X1 slot is more than enough for a wireless card.
In order to further explain this, let us read a bit more in depth.
Also Read: Best Motherboard with Built In WiFi
Which PCIe Slot for Wireless Card?
As mentioned earlier, the X1 slot is more than enough for the contemporary WiFi 5 and WiFi 6 protocols.
This is because the PCIe Version 3.0 has a transfer speed of about 1 GB/sec per lane. This is sufficient to support the transfer speed requirement for the wireless add in cards.
HOWEVER, it should be noted that while ideally X1 slot should be used, you CAN fit the Wireless card in other larger slots i.e the X4, X8 or even the X16.
But, you should also note that installing the WiFi card in a larger PCIe slot will not give any kind of performance boost.
Plus, doing so would mean that you will have to sacrifice precious larger PCIe slots that can otherwise be used for larger expansion cards like RAID controllers of SSD Add In Cards.
For instance, a PCIe X16 is the largest slot available on a consumer grade motherboard. If you occupy that with a WiFi card that requires a mere X1 slot, you will have wasted a card that can be used for a graphics card instead.
Also Read: Best Motherboards with Bluetooth
Why is X1 Sufficient for a Wireless Card?
This has all to do with transfer speeds.
The transfer of PCIe slot differs from version to version. Currently, the most common PCIe version is the Version 3.0. However, on older or entry level motherboard you may find some slots operating at Version 2.0 as well.
The above chart shows that a typical X1 slot with PCIe V3 has transfer speeds of 984.6 MB/s (Mega Bytes Per Second). This is approximately 1 GB/s.
1 Gega Byte Per Second (GB/s) is equal to 8000 Mega bits Per Second (Mb/s) or 8 Gb/s. Note, it is important to realize the difference between Bytes and bits. One Byte has 8 bits.
This means that an X1 slot would be more than sufficient for any device that requires a transfer rate of 8 Gb/s.
Now let us compare this to the transfer rates of WiFi cards.
- WiFi 5, also known as 802.11ac, is the current generation of WiFi with transfer rate of about 1.8 Gbps.
- WiFi 6, also known as 802.11ax, is the latest generation to hit the market and has transfer speed of 2.4 Gbps.
As such even the transfer speed of WiFi 6 with 2.4 Gb/s is far lower than the maximum supported transfer speeds of PCIe v3.0 X1 slot which is about 8 Gb/s.
Hence installing the WiFi card in any other larger slots will be completely unnecessary.
How does the X1 Slot look like?
PCIe X1 is the smallest PCIe slot that you find on your motherboard.
The image above shows the size difference between a full size X16 slot and an X1 slot.
Will a WiFi Card fit Into a X4, X8 or X16 Slot?
As mentioned earlier, yes you can. However, doing so will not give any kind of performance boost to your WiFi card.
Also you will have potentially wasted a larger slot which could otherwise be used for a more demanding expansion card.
However, if you do not have any X1 slot available for use, then go ahead and slap in the WiFi card in any available PCIe slot.
Do You Need to Provide External Power to the Wireless Card?
No, you do not. Unlike the graphics cards that are installed on PCIe X16 that require direct power from the PSU, the WiFi card does not.
WiFi card consumes very little power and therefore, they can be powered through the PCIe slot itself.
Making Sure You have Enough PCIe Lanes
This is a very important consideration when installing newer PCIe devices to your computer
Every PC has only a limited amount of PCIe lanes. Using the PCIe X1 slot means that you are using one PCIe lane of your computer.
The total amount of PCIe lanes are determined by the processor you have as well as your motherboard chipset.
You can find out about the amount of lanes you have by looking at the processor and the motherboard chipset specsheet.
In order to install a WiFi Card and make it work, you need to make sure you have one PCIe lane available to you.
Typically an average processor offers 16 PCIe lanes and the motherboard may offer 4 or more PCIe lanes. So lets say you have 20 PCIe lanes available to you.
Say you install a graphics card on an X16 slot and a RAID controller on an X4 slot. They both will occupy 16 and 4 lanes respectively, totaling 20.
Hence, installing a WiFi card, even if you have a free X1 slot available, will not allow it work since you only have 20 PCIe lanes available in total.
On the other hand, if you only have a single graphics card installed, then you can go ahead with using the X1 slot for your WiFi. With this configuration you will have occupied 17 out of 20 lanes (16 for graphics card and 1 for WiFi card).
Therefore, you will still have 3 PCIe lanes available which can be used for other devices.
In short, you will need to manage your total PCIe lanes and the amount of expansion cards you install.
Here we looked at a common question asked by those who are new to PCIe configuration and expansion cards i.e which PCIe slot for wireless card is suitable?
The simplest answer is, the X1 slot and we looked at the reason why above. However, we also mentioned that if you do NOT have an X1 slot, you can go ahead and install the WiFi card in X4, X8 or even on an X16 slot but you will not see any performance boost.
We also mentioned that before installing any PCIe expansion card like the WiFi card, it is essential that you make sure your PC has enough PCIe lanes to support your card.
This is especially try if you already have a plethora of devices connected to your PCIe slot. In case if you have none, or if you only have a single graphics card connected only, then there is a high certainty that you will have enough PCIe lanes left to support the WiFi expansion card as well.