The easiest way to know how many PCIe slots you have is to check on the motherboard’s manufacturer’s website. Another way is to look at the user guide that came with the board. Using third-party software can also help, and for the more technically inclined, you can open up the motherboard and count how many slots you have manually.
Motherboards come with PCIe slots which allow users to install extra hardware to improve or extend the performance of the system. These are known as PCIe expansion cards, or add-in card.
But, PCIe slots are limited depending on the motherboard model. Their sizes also differ. If you want to know how many PCIe slots do I have, there are a couple of ways to go about it and we will discuss these below.
It is also worth noting that the amount of slots you have DOES NOT correspond to the amount of PCIe lanes you have.
It is recommended that you check your motherboard slots as well as the amount of PCIe lanes you have before you go about investing in an expansion card.
To learn in detail about what PCIe lanes are and how many you have we recommend reading this article.
Types of PCIe Slots
Before we talk about how many slots you have, it is important to learn what kind of PCIe slots are available out there.
There are generally 4 types of PCIe slots:
- x16 Slot – This is the largest slot with 16 lanes. Generally used for graphics card.
- x16 Slot with x8 bandwidth – This has the size of an x16 slot, but only half the PCIe lanes. It is also used by graphics card often for multi-GPU configuration.
- x4 Slot – This has 4 PCIe lanes – It is used for more demanding cards like 10G Ethernet, NVMe M.2 SSD Expansion, 4K video capture cards etc
- x1 Slot – This has a single PCIe lane – It used for weaker card like sound card, 1G network adapter, USB hubs etc.
Also Read: 10 Things That Can Be Plugged in PCIe Slots
How Many PCIe Slots Do I Have?
Determining the number of PCIe slots you have on your computer isn’t too hard. You just need to know where to look for and you will come up with answers very quickly, but here are a few easy ways:
- Check the Manufacturer’s Website
- Consult Motherboard User Guide or Manual
- Use a Third Party Software
- Manual Inspection
1. Check the Manufacturer’s Website
Checking the manufacturer’s website is the easiest way to access accurate information about your motherboard.
You will need to know the model number of your motherboard though to look it up online.
Finding Out Motherboard Model Number
The simplest way to check out the make and model of your motherboard is to open System Information service on Windows.
To do this, simply type “System Information” in the search bar of your Windows PC and open the service. Here, look for column where it says “System Manufacturer” and “System Model”. You can also look into columns: “Baseboard Manufacturer”, and “BaseBoard Product”.
From here you should be able to figure out the make and model of your motherboard.
The other way is to physically check the motherboard. Almost all motherboard have the make and model number written on them.
Head Over to Manufacturer Site
Once you have the make and model number, open up Google and search for it.
Find the model matching yours and look for its specifications page or tab. This will have various information about the motherboard, including its PCIe slots, their slot types, and in some cases, a visual representation of where exactly on the motherboard a specific PCIe slot is.
The official specifications like the one above not only tells you many PCIe slots you have but also what type, size and version they are.
For instance, this motherboard has 1 x PCIe x16 slot and another PCIe x16 slot working in x4 bandwidth. Meaning despite the second slot having a full 16x size, it only offer 4 lanes. (To a common observer, both x16 slots would seem to have the same amount of lanes, however, in reality this is not the case. Hence looking up specifications is very important).
The specifications also says that it offers 3 x smaller x1 PCIe slots for smaller cards like network adapter, sound card etc.
In addition to that, since this is an older board, it also offers the old PCI slots (these are more less obsolete now).
Moreover, the specifications also tell you about the PCIe version. This motherboard conforms to the older PCIe v2.0.
Also Read: PCIe 3.0 vs 2.0
PCIe Slots and PCIe Lanes
It is worth noting here that the amount of PCIe slots you have does not correspond to how many PCIe lanes you have.
Basically, a PCIe lane is a pipeline that transfers data to and from a PCIe slot. The amount of pipelines you have are limited and they depend upon the type of motherboard and CPU you have: (Read: How to Check How Many PCIe Lanes Do I Have?)
So a typical PC can have 20 PCIe lanes. Each expansion card installed on the PCIe slot has a specific requirement for how many PCIe lanes it requires to operate optimally.
A graphics card, for example, requires 16 lanes. Ethernet adapter on the other hand requires a single PCIe lane most of the time.
So if your motherboard offers 1 x X16 slot with 16 lanes, 1 x X4 slot with 4 lanes and 3 x X1 slots with one lane each, but if your system only has 20 PCIe lanes, then some of the slots will NOT be operable.
Again, the exact configuration of the board and the slots is provided by the motherboard specification sheet.
Also Read: What are PCIe Lanes?
2. Consult Motherboard User Guide or Manual
Another fairly simply method to check the kind and amount of PCIe slots you have is to check the user guide/manual.
Your motherboard will likely ship with a user guide. Not only does this document tell you how to take care of your motherboard, but it is also a treasure trove of information regarding the pieces of the motherboard.
To find how many PCIe slots do I have from the user guide, read through it, and if it has a section on PCIe slots, skip over to it.
Many user guides also clearly label each and every component on the motherboard.
The user guide can be your first stem to get information on your motherboard, and it can be so beneficial that you won’t need to visit the manufacturer’s website or any other online resource.
Unfortunately, if you have an older PC, there are chances that you may have misplaced it, well don’t fret as you can always use the other methods listed here.
3. Use a Third Party Software
Some third party applications can scrape a lot of information from your hardware, including information about how many PCIe slots you have, and present it to you.
That said, you can use a program like HWiNFO on Windows to find out how many PCIe slots you have. This is a FREE software fortunately.
Check PCIe Slot Using HWiNFO
Note that the following demonstration and sample is for checking PCIe version and slot on a laptop motherboard. For a desktop, the same procedure can work.
Download and install HWiNFO from their website. Then, run it on your computer.
Once downloaded, you will be given two run files HWiNFO32.exe and HWiNFO64.exe. Select the run file depending upon your system architecture.
Also Read: How to Check What is My System Architecture?
This will open a small option window. DO NOT select any check boxes on the side and simply press RUN.
This should open a comprehensive system information.
Once the program runs, expand the “Motherboard” section on the left. Then look for an option called “System Slot”. In the case of my laptop this is located under “Motherboard” -> “SMBIOS DMI” -> “System Slot”
This should open up a list of PCIe slot you have. Select any. On the right right hand side, it should tell you its information such as its size, as well as the version.
So in the case of my laptop, I have a single free x1 slot. Its version is PCIe 3.0.
On a typical desktop motherboard, the list of slots will be more comprehensive.
However, sometimes the PCIe slot information shown in HWiNFO may not always be accurate as this post explains.
4. Manual Inspection
If the motherboard is new and has not yet been installed in a computer, or if it has already been installed but you can easily get access to it, you can go ahead and check the slots manually, and count them to find out just how many you have.
As mentioned earlier in this article, there are various PCIe slot sizes on the motherboard, denoted by X1, X4, X8, and X16 which refers to the number of lanes.
Nevertheless, a slot may have an X16 size but only have 4 lanes instead of 16 as is the case with Gigabyte GA-p67A-UD3 below.
Image Source: This motherboard has 2 x PCIe x16 slot (Blue ones), however, the second PCIe x16 slot only operates at x4 bandwidth. The other ports it has are 3 x X1 slots and 2 x PCI slots (These are now obsolete).
For a motherboard that’s already installed, you will need to switch off the computer and unplug it from power before opening it up. You can take extra measures to avoid electrostatic damage.
Once you have access to the motherboard, finding out exactly how many PCIe slots do I have will simply involve identifying the slots and counting them. You may even identify the size of the slot if you need that information.
While, as mentioned earlier, this is not the most accurate method for figuring out the type of PCIe slot you have, you can reduce your chances of error by understanding some general rules for consumer grade motherboard:
- First PCIe x16 slot always has 16 lanes bandwidth – use this slot for graphics card.
- Second PCIe x16 slot (if available) is the only confusing aspect mostly as it can either have x8 or x4 bandwidth.
As seen above, there are many ways to check how many PCIe slots do I have. If you are a new PC builder or if you are planning on installing a new device to your system, then understanding the PCIe slots is important.
However, understanding PCIe slots is only one part of the equation. You also have to understand PCIe lanes and lane count.
We have a comprehensive knowledge base here on PCIe that you can check out