PCIe 3 vs PCIe 4 SSD: Is It Worth Upgrading

What Are PCIe 3 and PCIe 4?

PCIe (Peripheral Component Interconnect Express) is the interface that connects components like graphics cards and NVMe SSDs to the motherboard. Each generation doubles the theoretical bandwidth per lane. PCIe 3.0 offers about 1 GB/s per lane, while PCIe 4.0 doubles that to about 2 GB/s per lane. For NVMe SSDs, which typically use four lanes, this means PCIe 4.0 can deliver up to 8 GB/s of theoretical bandwidth, compared to 4 GB/s for PCIe 3.0.

In practice, the actual transfer speeds you see depend on the SSD's controller and NAND flash, not just the interface. A PCIe 4.0 SSD can reach sequential read speeds of around 7,000 MB/s, while a PCIe 3.0 SSD tops out around 3,500 MB/s. These numbers are theoretical maximums; real-world performance varies.

When you choose a gaming PC, the storage interface is part of the specification. For a detailed look at what to check, see what to check in a gaming PC for storage interface.

Gaming Load Times: PCIe 3 vs PCIe 4

For gaming, the primary benefit of a faster SSD is reduced load times. However, the difference between PCIe 3 and PCIe 4 in load times is often small. Most games load assets in a way that doesn't fully saturate the bandwidth of a PCIe 3.0 SSD. The bottleneck is usually the game engine's data processing, not the storage interface.

In large open-world games, you might notice a slight improvement with PCIe 4, but it's not a dramatic jump. The load times are already fast on a good PCIe 3 NVMe SSD, often just a few seconds. The difference between a 3,500 MB/s and a 7,000 MB/s SSD in a game load is typically less than a second.

If you're building a new gaming PC, a PCIe 4 SSD is a good choice for future-proofing, but it's not essential for current games. For an existing system with a PCIe 3 slot, upgrading to a PCIe 4 SSD won't help unless the motherboard also supports PCIe 4.

For more on how much storage you need, see how much SSD storage is enough for gaming.

Transfer Speeds and File Operations

Where PCIe 4 shines is in file transfers and other tasks that involve moving large amounts of data. Copying a large game installation folder, rendering video, or working with high-resolution assets will be noticeably faster on a PCIe 4 SSD. The sequential read and write speeds are double that of PCIe 3, so tasks that are bandwidth-bound benefit significantly.

For example, moving a 50 GB game folder from one drive to another could take half the time on a PCIe 4 SSD compared to a PCIe 3. This is a real advantage for users who frequently reinstall games or manage large libraries.

Random read and write speeds, which matter for loading many small files, also improve with PCIe 4, but the difference is less pronounced. The controller and NAND technology play a bigger role here.

If you're comparing SSDs, you might also want to understand the difference between SATA and NVMe. See SATA vs NVMe SSD for gaming.

Compatibility and System Requirements

PCIe 4.0 SSDs are backward compatible with PCIe 3.0 slots, but they will run at PCIe 3.0 speeds. To get the full benefit of a PCIe 4.0 SSD, you need a motherboard with PCIe 4.0 M.2 slots and a compatible CPU. Most modern platforms, such as AMD AM5 and Intel LGA 1700, support PCIe 4.0, but older systems may not.

When choosing a gaming PC, check the motherboard's M.2 slot specifications. If the slot is PCIe 4.0, you can install a PCIe 4.0 SSD and get the faster speeds. If it's PCIe 3.0, a PCIe 3.0 SSD is the practical choice.

Also, ensure the SSD's form factor (M.2 2280) fits the slot. Most gaming PCs have at least one M.2 slot, but some budget models may only have PCIe 3.0 support.

For a broader guide on what to check in a prebuilt, see what to check before buying a prebuilt gaming PC.

What to Pick for Your Play

For most gamers, a PCIe 3.0 NVMe SSD is more than enough. It offers fast load times and good transfer speeds for everyday use. If you're on a budget or have a PCIe 3.0 motherboard, there's no need to upgrade.

If you're building a new high-end gaming PC, or if you frequently move large files, a PCIe 4.0 SSD is a worthwhile investment. It provides faster transfer speeds and future-proofs your system for upcoming games that may take advantage of the extra bandwidth.

Consider your gaming habits. If you play competitive shooters where every second counts, the difference in load times is negligible. If you play large open-world games and want the fastest possible loading, PCIe 4 is a nice-to-have, but not a must.

For a deeper dive into PCIe generations, see what PCIe version is enough for gaming.

What to pick for your play

Questions

Is PCIe 4 SSD worth it for gaming?

For gaming, the difference in load times between PCIe 3 and PCIe 4 is often small. PCIe 4 is worth it if you want the fastest transfer speeds for file operations or future-proofing, but for most games, PCIe 3 is sufficient.

Can I use a PCIe 4 SSD in a PCIe 3 slot?

Yes, PCIe 4 SSDs are backward compatible with PCIe 3 slots, but they will run at PCIe 3 speeds. You won't get the full performance unless the motherboard supports PCIe 4.

What is the difference in transfer speeds?

PCIe 4.0 NVMe SSDs can reach sequential read speeds of up to 7,000 MB/s, while PCIe 3.0 SSDs top out around 3,500 MB/s. This means file transfers and large data operations are roughly twice as fast on PCIe 4.

Do I need a PCIe 4 SSD for next-gen games?

Current games don't require PCIe 4, but future games may take advantage of the extra bandwidth. If you want to be prepared, a PCIe 4 SSD is a good investment, but it's not essential for today's titles.