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Can I Use a PCIe 3.0 Graphics Card in a PCIe 4.0 Slot?

Learn whether you have to upgrade your PCIe 2.0 or PCIe 3.0 graphics card to work in a newer PCIe 4.0 motherboard slot and how graphics performance could be affected.

NVidia Geforce RTX Graphics Card in a Computer Caspar Camille Rubin / Unsplash

Last Updated: December 28, 2021

Written by Kevin Jones

Newer graphics card prices are inflated by about 100% of MSRP due to various factors, including chip shortages triggered by the pandemic and high demand from crypto miners and holiday shoppers. Based on this, I'm sure that many people are wondering whether to hold off on buying a new graphics card while they upgrade the rest of their system.

Chipmakers indicate that chip shortages could last into at least the end of 2022, so plan accordingly. If you are considering upgrading, you may be able to save a little by selling your old graphics card at inflated prices.

Let's dig into whether you can keep using your old graphics card in your new system.

Can I Use a PCIe 3.0 Graphics Card in a PCIe 4.0 Motherboard Slot?

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An older PCIe 3.0 graphics card will work in a PCIe 4.0 motherboard slot at PCIe 3.0 speeds. Similarly, an old PCIe 2.0 graphics card will work in a PCIe 4.0 motherboard slot at PCIe 2.0 speeds.

For PCIe 4.0 graphics cards, maximum graphics throughput can only barely exceed that of PCIe 3.0. For this reason, the benefits of upgrading your graphics card to PCIe 4.0 will be minor. However, other differences between PCIe 4.0 and PCIe 3.0 graphics cards could impact performance, unrelated to the PCI-Express version.

PCI-Express versions are backward compatible, meaning that you can use a PCIe 4.0 graphics card or storage device on a PCIe 3.0 or PCIe 2.0 system. However, PCI-Express will use speeds based on the lowest of the two versions for communication. For example, if you use a PCIe 4.0 video card with a PCIe 3.0 system, the video card would be running at PCIe 3.0 speeds.

Reducing the PCIe version would halve the max potential bandwidth. However, you may not experience a performance impact if your device is not using the available bandwidth.

You can refer to the following table to determine the bandwidth limit and decide whether that is adequate for your needs.

PCI-Express Speeds (Rounded)
x1 Bandwidthx2 Bandwidthx4 Bandwidthx8 Bandwidthx16 Bandwidth
PCIe 1.0 250 MB/s 500 MB/s 750 MB/s 2 GB/s 4 GB/s
PCIe 2.0 500 MB/s 1000 MB/s 2 GB/s 4 GB/s 8 GB/s
PCIe 3.0 1 GB/s 2 GB/s 4 GB/s 8 GB/s 16 GB/s
PCIe 4.0 2 GB/s 4 GB/s 8 GB/s 16 GB/s 32 GB/s
PCIe 5.0 4 GB/s 8 GB/s 16 GB/s 32 GB/s 63 GB/s
PCIe 6.0 8 GB/s 16 GB/s 32 GB/s 63 GB/s 126 GB/s

PCIe versions are also forward compatible, meaning that you can use a newer PCIe device with an older system. Similarly, PCI-Express will use speeds based on the lowest of the two versions for communication.

Check out my recommended PCIe 4.0 CPUs and Motherboards below.

Intel Core i9-11900K Intel Core i9-11900K Check Price on Amazon Amazon Affiliate Link

Intel has released their PCIe 5.0 CPUs. Check out Which Intel and AMD CPUs Support PCIe 5.0? and Is PCIe 5.0 Worth It? for details.

CPUs that support PCIe 5.0 also support PCIe 4.0 and PCIe 3.0 devices.

Is PCIe 4.0 Worth It for Gaming?

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The performance improvement when upgrading graphics to PCIe 4.0 from PCIe 3.0 is currently pretty minor.

It is worth the upgrade to PCIe 4.0 for gaming if you:

  • Want to get every bit of extra performance out of a PCIe 4.0 graphics card
  • Want to future-proof your system
  • Want to free up PCIe lanes for other devices

Check out the complete list of CPUs supporting PCIe 4.0 in Which Intel and AMD CPUs Support PCIe 4.0?.

Check out the complete list of CPUs supporting PCIe 5.0 in Which Intel and AMD CPUs Support PCIe 5.0?.

Which Desktop Graphics Cards Support PCIe 4.0?

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Both Nvidia and AMD graphics cards supporting PCI-Express 4.0 are available.

All graphics cards with Nvidia's GeForce RTX 30 series GPUs support PCIe 4.0.

All graphics cards with AMD's Radeon RX 5000 and Radeon RX 6000 series GPUs support PCIe 4.0.

EVGA GeForce RTX 3060 Ti XC Gaming EVGA GeForce RTX 3060 Ti XC Gaming Check Price on Amazon Amazon Affiliate Link

List of GPUs That Support PCIe 4.0

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Nvidia GPUs

Nvidia PCIe 4.0 GPUs
Nvidia GeForce RTX 3000 Series
Desktop PCIe 4.0 x16 GPUs
GeForce RTX 3060, RTX 3060 Ti, RTX 3070, RTX 3070 Ti, RTX 3080, RTX 3080 Ti, RTX 3090
Nvidia RTX Ax000 Series
Workstation PCIe 4.0 x16 GPUs
RTX A2000, RTX A4000, RTX A5000, RTX A6000
Nvidia GeForce 20 Series
Mobile PCIe 4.0 x4 GPUs
GeForce MX450
Nvidia GeForce 30 Series
Mobile PCIe 4.0 x16 GPUs
GeForce RTX 3050, RTX 3050 Ti, RTX 3060, RTX 3070, RTX 3080

Find PCIe 4.0 Nvidia Graphics Cards on Amazon (affiliate link).

AMD GPUs

AMD PCIe 4.0 GPUs
AMD Radeon RX 5000 Series
Desktop PCIe 4.0 x8 GPUs
Radeon RX 5300, RX 5300 XT, RX 5500, RX 5500 XT
AMD Radeon RX 5000 Series
Desktop PCIe 4.0 x16 GPUs
Radeon RX 5600, RX 5600 XT, RX 5700, RX 5700 XT, RX 5700 XT 50th Anniv. Ed.
AMD Radeon RX 6000 Series
Desktop PCIe 4.0 x8 GPUs
Radeon RX 6600, RX 6600 XT
AMD Radeon RX 6000 Series
Desktop PCIe 4.0 x16 GPUs
Radeon RX 6700 XT, RX 6800, RX 6800 XT, RX 6900 XT
AMD Radeon Pro 5000M Series
Mobile Workstation PCIe 4.0 x16 GPUs
Radeon Pro 5300M, Pro 5500M, Pro 5600M
AMD Instinct Series
Server PCIe 4.0 x16 GPUs
Radeon Instinct MI60, AMD Instinct MI100, AMD Instinct MI250, AMD Instinct MI250X

Find PCIe 4.0 AMD Graphics Cards on Amazon (affiliate link).

Our Favorite PCIe 4.0 CPUs and Motherboards

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Best AMD High-Frequency CPU: AMD Ryzen 9 5900X

  • Up to 4.8 GHz: perfect for games, video editing, and high-intensity tasks.

  • 12 cores / 24 threads: High core count for the frequency! This combination makes it a great all-around system that can handle almost any job.

  • Check the latest price of the AMD Ryzen 9 5900X on Amazon (affiliate link).

    AMD Ryzen 9 5900X AMD Ryzen 9 5900X Check Price on Amazon Amazon Affiliate Link
  • For the AMD Ryzen 9 5900X CPU, you'll need a 5000 series motherboard with the X570 chipset to support PCIe 4.0.

  • Our recommended motherboard to pair with the Ryzen 9 5900X is MSI's MAG X570 TOMAHAWK WIFI Motherboard: MSI MAG X570 TOMAHAWK WIFI MSI MAG X570 TOMAHAWK WIFI Check Price on Amazon Amazon Affiliate Link

    • PCIe 4.0 support
    • One 2.5 Gb Ethernet port is faster than most Internet speeds, with room to spare for file transfers.
    • Two NVMe M.2 slots both run at PCIe 4.0 speeds.
    • Wi-Fi 6 provides great Wi-Fi speeds (not Wi-Fi 6E, but still really good).
    • USB 3.2 Gen 2 offers 10 Gbps USB speeds.
    • Check the latest price of the MSI MAG X570 TOMAHAWK WIFI Motherboard on Amazon (affiliate link).

Best Intel High-Frequency CPU: Intel Core i9-11900K

  • Up to 5.3 GHz: perfect for games, video editing, and high-intensity tasks.

  • 8 cores / 16 threads: Quite a few cores considering the frequency! This combination makes it a great all-around system that can handle almost any task.

  • You'll want to use a good cooler, as the "Thermal Velocity Boost Frequency" feature will improve your clock speed based on how cool you can keep it.

  • Virtualization features make it great for running virtual machines.

  • Check the latest price of the Intel Core i9-11900K on Amazon (affiliate link).

    Intel Core i9-11900K Intel Core i9-11900K Check Price on Amazon Amazon Affiliate Link
  • For the Intel Core i9-11900K CPU, you'll need a motherboard with the Z590 chipset to support PCIe 4.0.

  • Our recommended motherboard to pair with the i9-11900K is ASUS's ROG Maximus XIII Hero: ASUS ROG Maximus XIII Hero ASUS ROG Maximus XIII Hero Check Price on Amazon Amazon Affiliate Link

    • PCIe 4.0 support
    • Wi-Fi 6E makes it easy to reach the fastest speeds and future-proof your Wi-Fi system.
    • Four NVMe M.2 slots, which is a lot! (Only two of them run at PCIe 4.0 speeds)
    • Two 2.5 Gb Ethernet ports are faster than most Internet speeds with room to spare for file transfers.
    • USB 3.2 Gen 2x2 offers 20 Gbps USB speeds!
    • Check the latest price of the ASUS ROG Maximus XIII Hero on Amazon (affiliate link).

Best High-Core CPU: AMD Ryzen Threadripper 3990X

  • 64 cores / 128 threads: Insane number of cores/threads.

  • This CPU is going to be best for high-intensity multi-threading such as:

    • 3D graphics rendering (e.g., Blender/3DS Max/Maya)
    • CAD design, simulation, and visualization (e.g., AutoDesk Inventor)
    • Software that does a lot of physics analysis
  • Due to the high price, this CPU is best for business use-cases.

  • Check the latest price of the AMD Ryzen Threadripper 3990X on Amazon (affiliate link).

  • AMD Ryzen Threadripper 3960X (affiliate link) is a backup option if this one isn't in stock and for lower budgets.

    AMD Ryzen Threadripper 3990X AMD Ryzen Threadripper 3990X Check Price on Amazon Amazon Affiliate Link
  • For the AMD Ryzen Threadripper 3990X CPU, you'll need a motherboard with the TRX40 chipset to support PCIe 4.0.

  • Our recommended motherboard to pair with the AMD Ryzen Threadripper 3990X is ASUS's ROG Zenith II Extreme Alpha: ASUS ROG Zenith II Extreme Alpha ASUS ROG Zenith II Extreme Alpha Check Price on Amazon Amazon Affiliate Link

    • PCIe 4.0 support
    • Five NVMe M.2 slots all run at PCIe 4.0 seeds, which is insane!
    • One 10 Gb Ethernet port would allow you to transfer a 1 GB video file in under a second!
    • 1 USB 3.2 Gen 2x2 offers 20 Gbps USBs speeds; 9 USB 3.2 Gen 2 ports provide 10 Gbps; 8 USB 3.2 Gen 1 ports provide 5 Gbps; 3 USB 2.0 ports
    • Wi-Fi 6 provides great Wi-Fi speed (not Wi-Fi 6E, but still really good).
    • Bluetooth 5.0 is great for streaming music to Bluetooth headphones.
    • Check the latest price of the ASUS ROG Zenith II Extreme Alpha on Amazon (affiliate link).

Best Value CPU: Intel Core i5-11600K

  • Half the price of the i9-11900K, but still excellent performance at up to 4.9 GHz.

  • 6 cores / 12 threads: There are a decent number of threads to make it good at everyday multi-threading tasks, such as having tons of browser windows open.

  • Check the latest price of the Intel Core i5-11600K on Amazon (affiliate link).

  • Intel Core i5-11600KF (affiliate link) is a backup option if this one isn't in stock. It is the same other than the lack of integrated graphics support.

    Intel Core i5-11600K Intel Core i5-11600K Check Price on Amazon Amazon Affiliate Link
  • For the Intel Core i5-11600K CPU, you'll need a motherboard with the Z590 chipset to support PCIe 4.0.

  • Our recommended motherboard to pair with the i5-11600K is MSI's Z590 PRO WiFi ProSeries motherboard: MSI Z590 PRO WiFi ProSeries MSI Z590 PRO WiFi ProSeries Check Price on Amazon Amazon Affiliate Link

    • PCIe 4.0 support
    • Wi-Fi 6E makes it easy to reach the fastest speeds and future-proof your Wi-Fi system.
    • Bluetooth 5.2 is great for streaming music to Bluetooth headphones.
    • Three NVMe M.2 slots, which is pretty good! (Only one of them runs at PCIe 4.0 speeds)
    • Two 2.5 Gb Ethernet ports are faster than most Internet speeds with room to spare for file transfers.
    • USB 3.2 Gen 2x2 offers 20 Gbps USB speeds!
    • Check the latest price of the MSI Z590 PRO WiFi ProSeries on Amazon (affiliate link).

Multiple PCIe Versions for CPU/Motherboard

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Some CPUs and motherboards provide PCI-Express lanes at multiple PCIe versions. In these cases, you can choose which devices need the most bandwidth to decide which should be connected to the highest version PCIe lanes. While laying out your system, keep in mind that PCIe speeds will be based on the lowest PCIe version between the slot/port and the device.

Can I Use an x4 or x8 Card in an x16 PCIe Slot?

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You can use PCIe cards of a lower lane width (e.g., x2, x4, or x8) in a higher lane width slot (e.g., x16).

PCI-Express will negotiate how many lanes will be used, and your card will work at its full speed, assuming the PCIe slot has the same or higher PCIe version.

Other Considerations When Building a PC

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Want to brush up on other new technologies to consider when building a computer? Check out these articles:

Learn More About PCI-Express

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Want to brush up on the latest PCIe products, versions, and features? Check out the articles in this PCI-Express series: