What Is PCIe – 8 Advantages & Disadvantages

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What Is PCIe? The computer bus, or which is responsible for carrying data to and from the PC to you uses different channels for various sorts of data. Check out advantages and disadvantages of it.

You might have already read about the SATA interface on our page, and now it is time to talk about a universal interface through which you can utilize your PC’s expandability.

Hence, our topic today is about PCIe slots.


  • PCIe offers much larger bandwidth and higher data transfer speed due to the higher number of lanes.
  • PCIe offers more utility and less latency.
  • The power consumption of PCI express is higher than usual which results in faster battery drain in laptop computers.
  • PCI express is expensive and lacks specialization.
  • PCIe only supports modern devices.

What is PCIe?

What is PCIe

PCIe or PCI Express is the abbreviated form of Peripheral Component Interconnect Express, which is a form of computer bus expansion interface that can be used to add several useful components into your PC like a second GPU, WIFI adapters, SSD drives, RAID cards, etc.

It has replaced the older PCI and AGP slots. The PCI slot could be used to add other peripheral components, while the AGP had a sole purpose of adding a video card into your system.

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Thus, the use of PCIe has therefore reduced the need for multiple expansion ports, and you can use only one universal interface to add multiple other parts.

Brief History of PCIe

The PCI was introduced as a computer bus interface in 1991 and has gone through many improvements since then.

It is, in fact, the forefather of the PCIe cards we are talking about today, and thus share a common history.

Now the PCI Express has been in use since 2001, and the very first PCIe 1.0a had a speed of 250 MB/s per lane and transfer rates of about 2.5 GT/s (here GT refers to GigaTransfers).

Then two other versions were launched by 2010, and the most used version today is PCIe 3.0.

Newer versions are also present like the 4.0 and 5.0, while you may also come to know about the 6.0 within 2022.

How Does It Work?

As said above, the PCIe has different lanes for data transfer. The more number of lanes, the greater is the bandwidth, and hence the faster it is.

Though universal, PCIe is available in different physical forms. This refers to x1, x4, x8, and x16 lane types.

Each of these cards has different ports on themselves, while also there are different ports on the motherboard.

But, the good thing is that you can use an x8 GPU in an x16 slot, and vice versa.

In the second case, however, the GPU will have to work in a lesser bandwidth.

The PCIe works like a network, with a point-to-point connection. Check out difference between PCIe and SATA.

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This means that data moving out from the main bus goes through a switch, and then gets separated in a different direction towards the various devices that have asked for this data.

How Fast is PCIe?

Each lane on a PCIe 3.0 can reach speeds up to 1000mb/s.

The total speed and bandwidth of an x16 PCIe card is about 16 GB/s and 32 GB/s respectively, and now you know why your GPU requires this lane for functioning.

While some GPUs work in the x8 slot, adding your GPU to the x16 lane would provide you the best performance.

Advantages of PCIe

1. Larger Bandwidth

PCIe cards have up to 16 lanes for data travel, and this offers greater bandwidth. Thus, even high-performance GPUs can be fitted in PCIe slots.

2. Better Speed

In terms of speed, the PCIe is much faster than SATA and you will notice this difference as soon as you add the same SSD drive, first into the PCIe slot, and next in the SATA slot.

To be exact, the max speed in a PCIe 3.0 SSD is about 16Gb/s, while the SATA III can only reach up to 6 Gb/s.

Newer PCIe iterations like the PCIe 4.0 are even faster, but the upgrade will cost you.

3. More Utility

The PCIe interface can be used to add not only video cards but also WIFI adapters, SSD drives, etc and are thus multi-purpose.

4. Less Latency

Along with high speed, PCIe reduces the latency in a system.

They have a direct line to the peripheral components and so, while accessing large files or while working on servers and playing games, it is very useful.

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Disadvantages of PCIe

5. Greater Power Consumption

Although nothing too much, PCIe SSDs tend to consume more power when used for a long time.

This is also why using a SATA SSD on a laptop gives you a bit more battery backup.

6. Supports only newer devices

Most of the older computers will not support a PCIe SSD, and here the SATA interface comes handy with better support for older PCs.

7. Lack of Specialization 

The PCIe can carry different types of data, but it doesn’t have a specialization.

It doesn’t have standard storage commands like the other interfaces, which may pose problems.

8. Expensive

A principal drawback with the PCIe form of storage is that it is very expensive. For a budget buyer, it is not always possible to afford such an expensive SSD drive.


Now you know about PCIe, put it to you as simply as possible. Share this article and let us know whether this was helpful.