The short and simple answer to the question “do laptops have PCIe slots?” is a no. Unlike desktop motherboards, laptops DO NOT have PCIe slots.
While laptops do use the PCIe protocol for communication, they do not have physical PCIe slots for adding more cards into. As such, the expandability aspect of a laptop is far lower than that of a desktop.
Most of the critical components that use the PCIe bus are soldered onto the motherboard, hence, there is often no need for having extra PCIe slots on a laptop.
In this article, I will explain in detail how the PCIe devices on a laptop interact without any additional slots.
Do Laptops Use the PCIe Interface?
Yes, certainly they do.
PCIe protocol is basically enables communication between high speed devices such as graphics cards, SSDs, network cards etc and the rest of the components.
PCIe interface essentially comprises of PCIe lanes. Think of lanes as information highways through which the data sharing takes place.
Now any PC, be it a desktop or a laptop, has a limited amount of PCIe lanes. The amount of PCIe lanes depends upon what CPU and the motherboard chipset the PC has.
In addition to that, different devices require lower or higher amount of PCIe lanes depending upon how much data they generate.
Graphics cards require the most amount of lanes since they generate the highest amount of data.
In addition to that, like desktops, the performance of the PCIe interface on laptop also depends upon its version.
As such, a laptop that conforms to PCIe 4.0 standard would be able to utilize gen 4 devices such as Gen 4 NVMe SSDs which are much faster than their older Gen 3 PCIe 3.0 NVMe SSDs.
Read in Detail: What are PCIe Lanes?
You can see from the basic block diagram above that both the processor as well as the chipset provide PCIe lanes.
So Do Laptops Have PCIe Slots?
No they do not. They do not have the typical PCIe slots.
While a laptop does make use of the PCIe protocol, unfortunately, the PCIe lanes are not user accessible.
Meaning, there are no PCIe slots on a laptop’s motherboard for you to plug devices in and out from.
Commercial Laptop’s aren’t designed so that you may plug or replace devices in and out from it.
In order to install devices onto a laptop you would need devices with the mobile form factor.
Currently, the only available mobile expansion devices conform to the mini PCIe standard. These devices are rare and expensive AND you need to have a spare Mini PCIe port – which most laptops DO NOT.
A mini PCIe port offers only one PCIe lane.
In addition to that, the mini PCIe modules, as you can see above, are NOT intended for commercial PC. They are intended for industrial use or for embedded systems.
There simply isn’t a market large enough for PCIe expansion cards made for laptops.
Mini PCIe Slot is Laptops is Occupied with WiFi Card
Many laptops have a Mini PCIe slot. However, this PCIe slot is intended for the WiFi Card.
Hence removing the card would rid you of the essential WiFi connectivity.
Plus, it is not like you would be able to install a separate graphics card module on to this slot, Firstly, there are no mini PCIe graphics cards available.
Secondly, as mentioned, a mini PCie slot only offers a single PCIe lanes. Graphics card require 8-16 PCIe lanes.
The PCIe Components in Laptops are Built-in or Soldered
Since there are no PCIe slots, the PCIe devices such as the graphics card are soldered onto the motherboard itself.
They cannot be removed or replaced.
M.2 is the ONLY PCIe Slot Available
The only slot that may be available to you that uses the PCIe interface is the M.2 slot for installing NVMe SSDs.
These slots use four lanes and can ONLY accommodate SSDs with the M.2 form factor.
These are not compatible with the rest of the traditional PCIe devices.
How to Tell if Your Laptop Has Free PCIe Slot?
You can’t since laptop do not have the traditional PCIe slots.
As far the mini PCIe slots go, you will either need to open up your laptop, or refer to its motherboard technical sheet to figure out whether it has a spare mini PCIe slot.
Generally though, laptops DO NOT have a spare mini PCIe slot available either.
Mobile PCIe Express Module (MXM) – Allowed for GPU Upgrade
There was a time when NVIDIA made a push for the MXM or the Mobile PCIe Express Module technology to be adopted by the laptop market.
The MXM module was essentially a graphics card that could be plugged in and out of the its respective slot on the laptop’s motherboard.
This module essentially aimed to standardize the PCIe slot for graphics card on laptops. This way, the GPU would not have to be soldered onto the laptop’s motherboard.
MXM aimed to the solve the age old issue of mobile GPU upgradability.
However, despite NVIDIA’s push, this technology did not gain much traction since whether it was implemented or not on laptops was entirely manufacturer’s decision.
And the various laptop manufacturer’s failed to adopt this standard probably due to financial reasons.
If users are given the freedom to upgrade their GPU, that would result in increasing gains for NVIDIA and AMD, but diminishing gains for the manufacturer’s themselves.
In addition to that MXM graphics cards were simply too expensive to make them appealing to the users.
Also Read: Why Do Motherboards Still Have PS2 Ports?
So the for uninitiated, the simple answer to the question “Do laptops have PCIe slots?” is a simply a no. Laptops do NOT have PCIe slots.
They may, however, have M.2 slots for SSDs, which also use the PCIe interface.
But in case if you are wondering that you can upgrade your laptop just as you would upgrade a desktop by adding expansion cards on to it, then that is simply not possible.
Laptop’s aren’t designed to be nearly as flexible in terms of upgradability as desktops.