Do SSDs Impact GPU Performance?

Hopefully it isn’t a surprise to state that an NVMe SSD is the storage of choice if you’re building a high-performance PC. Along with fast memory and a powerful graphics card, the SSD has quickly become a mainstay of any system looking to offer the best performance. But does installing an SSD, or even multiple SSDs, adversely affect the performance of your graphics card? Given that NVMe SSDs utilize the same PCIe lanes as the graphics card, does this mean you won’t get the best performance from your GPU if you fill your system with SSDs?

The short answer is yes, it could, but (and it’s an important but) you won’t notice it in real terms. The slightly longer answer is what the rest of this article is about.

To understand what’s going on here, we need to look under the hood of your processor and the motherboard chipset it’s paired with. The CPU determines how many PCIe lanes are available for your graphics card and SSDs, as well as how many lanes are set aside for the motherboard chipset.

A real-world example will help make this clearer. Let’s look at the current favorite processor for PC gamers, the AMD Ryzen 7 9800X3D. This CPU has 28 native PCIe 5.0 lanes, four of which are reserved for connecting to the motherboard chipset, leaving 24 lanes for the focus of this article – 16 lanes are dedicated to the graphics card, four lanes to the first M.2 SSD slot, and the last four for any other PCIe slots or an additional M.2 connector.

Any other devices, such as networking, audio, and extra storage, are routed through the motherboard chipset, which connects to your CPU via the four PCIe lanes mentioned earlier. All clear? Hold that thought, because while the CPU may support these lanes, your motherboard must support them too, and that depends on its chipset.

The first thing that stands out here is the sheer number of AM5 motherboard chipsets available. We’re not here to get lost in the details of AMD’s motherboards, but it’s worth highlighting how much impact your choice of motherboard has on your system’s capabilities.

This table also highlights a few key differences, such as the fact that the X870E chipset supports USB4, whereas the B650E does not, although motherboard manufacturers can add support. It’s also useful for checking which chipsets support PCIe 5.0 graphics slots and how many other PCIe lanes are available. Motherboard manufacturers may use these lanes differently, some offering more M.2 slots for SSDs, more USB ports, or additional PCIe expansion slots. You’ll need to check your motherboard’s specifications to see how these lanes are allocated.

Now, back to our example. There’s no issue using a PCIe 5.0 graphics card, such as the recently released Nvidia GeForce RTX 5080, alongside a high-speed PCIe 5.0 SSD like the CORSAIR MP700 PRO SE 2TB. The CPU has lanes specifically set aside for this. But what happens if you add more SSDs? At this point, depending on your motherboard, the PCIe lanes for additional SSDs may be shared with those allocated to the graphics card, reducing it from 16 lanes to just eight, effectively halving the bandwidth.

Isn’t that a problem? Actually, no, not as much as you might think. Graphics cards have far more bandwidth than they use, especially with PCIe 5.0. A full 16x PCIe 5.0 connection provides an enormous 64GB/s (slightly less due to encoding), and even cutting that in half to 8x PCIe 5.0 still delivers 32GB/s – more than enough for normal use.

Testing shows that dropping to 8x PCIe 5.0 results in just a 1–2% reduction in frame rates, as confirmed by benchmarks from sources like Gamers Nexus and JayzTwoCents.

Even reducing the bandwidth further, down to PCIe 3.0 levels (16GB/s), still results in only a 2–4% drop in performance. While there may be niche scenarios where this reduction is noticeable, gaming performance remains largely unaffected.

It’s worth highlighting how PCIe bandwidth scales, as each new generation doubles throughput. Essentially, an x8 PCIe 5.0 connection is comparable to an x16 PCIe 4.0 connection.

So, to answer the original question: Will installing multiple SSDs impact GPU performance? Yes, but not in any meaningful way. However, if you want to ensure maximum performance, you should prioritize one or two larger SSDs rather than several smaller ones. This approach helps maintain optimal throughput for both gaming and file transfers.