PCIe 4.0 vs 3.0 SSDs: Real Performance Difference Test

You’ve seen the marketing claims. PCIe 4.0 SSDs boast sequential read speeds of 7,000 MB/s, practically doubling the 3,500 MB/s ceiling of their PCIe 3.0 predecessors. The spec sheets look impressive, and every manufacturer is eager to tell you their newest drive is twice as fast as last generation’s best.

But here’s what those spec sheets won’t tell you: sequential read speed is one of the least relevant metrics for most real-world computing tasks. I spent three weeks running benchmarks across gaming, file transfers, video editing, and everyday productivity workloads to find out exactly when PCIe 4.0 actually matters and when you’re paying extra for numbers you’ll never feel.

The results were surprising, even to me. Let me walk you through everything I found.

The Test Setup and Methodology

For this comparison, I tested two drives that represent the best of each generation. On the PCIe 4.0 side, I used the Samsung 990 Pro 2TB, which consistently hits advertised speeds of 7,450 MB/s read and 6,900 MB/s write. For PCIe 3.0, I used the Samsung 970 EVO Plus 2TB, one of the strongest Gen 3 drives ever made, with rated speeds of 3,500 MB/s read and 3,300 MB/s write.

The test system ran an AMD Ryzen 7 7800X3D on an MSI MAG X670E Tomahawk motherboard with 32GB of DDR5-6000 RAM. Both drives were tested in the primary M.2 slot (connected directly to the CPU) running Windows 11 23H2. Each test was run five times, with results averaged and the system rebooted between test types.

I intentionally chose Samsung’s best from each generation to keep the controller quality and NAND technology as close as possible. Using a budget Gen 4 drive against a premium Gen 3 drive (or vice versa) would skew the results.

Synthetic Benchmarks: Where the Gap Looks Enormous

Let’s start with the numbers that look most impressive on paper. In CrystalDiskMark 8.0, the generation gap is impossible to miss.

• Sequential Read (Q32T1): Gen 4 hit 7,410 MB/s vs. Gen 3’s 3,480 MB/s. That’s a 113% advantage.
• Sequential Write (Q32T1): Gen 4 managed 6,870 MB/s vs. Gen 3’s 3,290 MB/s. A 109% lead.
• Random Read 4K (Q1T1): Gen 4 reached 92 MB/s vs. Gen 3’s 78 MB/s. Only an 18% difference.
• Random Write 4K (Q1T1): Gen 4 posted 185 MB/s vs. Gen 3’s 162 MB/s. A 14% gap.

Notice something important here. Sequential performance roughly doubles, as expected. But random 4K performance at low queue depths, which is the metric that most closely mirrors everyday computing, shows a much more modest improvement. This pattern repeated itself throughout every real-world test I ran.

Gaming Performance: Prepare to Be Underwhelmed

Gaming is where most enthusiasts expect to see massive improvements from faster storage, especially with DirectStorage on the horizon. I tested boot-to-menu times, level load times, and texture streaming across six games.

Game Load Times (Average of Five Runs)

• Cyberpunk 2077 (save file load): Gen 4: 8.2 seconds | Gen 3: 8.9 seconds
• Baldur’s Gate 3 (campaign load): Gen 4: 14.1 seconds | Gen 3: 15.3 seconds
• Starfield (save load): Gen 4: 6.8 seconds | Gen 3: 7.4 seconds
• Call of Duty MW3 (map load): Gen 4: 11.2 seconds | Gen 3: 12.0 seconds
• Hogwarts Legacy (fast travel): Gen 4: 3.1 seconds | Gen 3: 3.5 seconds
• Final Fantasy XVI (chapter load): Gen 4: 5.4 seconds | Gen 3: 5.9 seconds

Across all six titles, the PCIe 4.0 drive averaged about 8% faster load times. In absolute terms, you’re saving less than a second in most cases. During actual gameplay, I could not detect any difference in texture pop-in or stuttering between the two drives. Frame rates were identical.

The PS5 requires at least a PCIe 4.0 NVMe drive for its expansion slot, which has led many PC gamers to assume Gen 4 is equally essential on desktop. It isn’t. PC games aren’t yet optimized to take advantage of the bandwidth, and most game engines bottleneck on decompression and CPU processing long before storage speed becomes a factor.

Large File Transfers: Where Gen 4 Earns Its Keep

This is the workload category where PCIe 4.0 genuinely pulls ahead in a meaningful way. I tested single large file copies and mixed file/folder copies between the test drive and a secondary NVMe drive (also Gen 4 capable).

File Transfer Results

• Single 50GB file copy: Gen 4: 8.1 seconds | Gen 3: 15.8 seconds (48.7% faster)
• 100GB game folder (mixed files): Gen 4: 29.4 seconds | Gen 3: 44.2 seconds (33.5% faster)
• 25GB ZIP archive extraction: Gen 4: 18.7 seconds | Gen 3: 26.1 seconds (28.3% faster)
• 4,000 small files (12GB total): Gen 4: 22.3 seconds | Gen 3: 25.8 seconds (13.6% faster)

When you’re moving large sequential files, the doubled bandwidth of PCIe 4.0 is very real. If you regularly shuffle around huge video files, disk images, or game backups, you’ll feel this difference every time. The advantage shrinks as file sizes decrease and file counts increase, since small file transfers are limited more by IOPS and latency than raw throughput.

Samsung 990 Pro 2TB NVMe SSD

Top-tier PCIe 4.0 performance with 7,450 MB/s reads, ideal for content creators who regularly move massive files

Check Price on Amazon

Content Creation and Productivity Workloads

This is where things get interesting, because the results varied dramatically depending on the specific application.

Video Editing (DaVinci Resolve 18)

I tested timeline scrubbing performance with 4K ProRes 422 HQ footage and export times for a 10-minute 4K project. Timeline scrubbing was indistinguishable between drives. Export time showed a small 6% advantage for Gen 4 (3:42 vs. 3:56), but the bottleneck was clearly the GPU and CPU encoding, not storage speed.

Where Gen 4 made a real difference was in importing and organizing large batches of raw footage. Copying 200GB of raw 4K clips into a project folder was noticeably faster.

Photo Editing (Adobe Lightroom Classic)

Importing 1,000 RAW files (42MP, ~60MB each) showed a 22% speed advantage for Gen 4. Generating 1:1 previews was almost identical, since that task is CPU-bound. Exporting 500 processed images as JPEGs showed only a 4% difference.

Software Compilation

Building the Chromium browser source code from scratch: Gen 4 completed in 47 minutes, Gen 3 in 49 minutes. The difference is negligible because compilation is overwhelmingly CPU-bound, with storage only mattering during the initial source tree read and final binary write.

Virtual Machines

Booting a Windows 11 VM from a 60GB VHDX file in VMware Workstation: Gen 4 reached the desktop in 11 seconds, Gen 3 in 14 seconds. This was one of the more noticeable differences in daily use, since VM files are large sequential reads that benefit directly from bandwidth.

Boot Times and Application Launches

Windows 11 cold boot (POST to desktop): Gen 4 took 14.8 seconds, Gen 3 took 15.6 seconds. You’d need a stopwatch to tell the difference.

Application launch times told a similar story. Adobe Premiere Pro opened in 6.2 seconds on Gen 4 and 6.7 seconds on Gen 3. Chrome with 15 tabs restored: 3.1 vs. 3.4 seconds. Microsoft Office suite: virtually identical. These applications are loading relatively small executables and libraries. They don’t push anywhere near the sequential bandwidth limits of even a Gen 3 drive.

When PCIe 4.0 Actually Matters

After all this testing, a clear pattern emerged. PCIe 4.0 provides meaningful, perceptible benefits in these specific scenarios:

• Moving files larger than 10GB regularly (video production, dataset management, backups)
• Working with virtual machine disk images
• Importing large batches of RAW photos or video clips
• Cloning or imaging drives
• Sustained sequential write workloads like database logging or security camera recording

For everything else, including gaming, application launches, OS responsiveness, web browsing, and general multitasking, the difference between Gen 4 and Gen 3 ranges from imperceptible to barely measurable.

My Recommendation: It Depends on Your Workload (and the Price Gap)

If you’re building a new system today and the price difference between a good Gen 3 drive and a good Gen 4 drive is minimal, get the Gen 4 drive. There’s no downside, and you’ll be ready if future software starts demanding more bandwidth. The current Gen 4 NVMe market has matured enough that prices have dropped considerably.

For a Gen 4 drive with excellent all-around performance, the WD Black SN850X is hard to beat. It trades blows with the Samsung 990 Pro in most benchmarks and often comes in at a slightly lower price point.

However, if you already have a quality PCIe 3.0 drive like the 970 EVO Plus or the WD Black SN750, upgrading to Gen 4 purely for speed is not a good use of your money. You’d be better off spending that budget on more RAM, a better GPU, or simply a larger capacity drive.

For budget-conscious builders who just want a reliable, fast NVMe drive and don’t work with huge files daily, a PCIe 3.0 drive still makes perfect sense. The Samsung 970 EVO Plus remains an excellent choice if you can find it, and it will feel identical to a Gen 4 drive in the vast majority of daily tasks.

Samsung 970 EVO Plus 1TB NVMe SSD

Still one of the best Gen 3 drives ever made, more than fast enough for gaming and everyday computing

Check Price on Amazon

What About PCIe 5.0?

PCIe 5.0 SSDs are starting to arrive, with drives like the Crucial T700 and Samsung 990 EVO Plus offering speeds beyond 12,000 MB/s. Before you ask: the same pattern applies, just more so. The jump from Gen 4 to Gen 5 doubles sequential bandwidth again, but random 4K performance improvements are modest, and real-world gaming and productivity benefits remain small for most users.

Gen 5 drives also run significantly hotter, often requiring large heatsinks, and carry a premium price. Unless your workflow involves sustained multi-gigabyte-per-second transfers, Gen 4 remains the sweet spot for performance per dollar in 2024 and into 2025.

Frequently Asked Questions

Can I use a PCIe 4.0 SSD in a PCIe 3.0 motherboard slot?

Yes, PCIe is backward and forward compatible. A Gen 4 drive will work perfectly in a Gen 3 slot. It’ll simply operate at Gen 3 speeds (capped around 3,500 MB/s). This is actually a solid strategy if you plan to upgrade your motherboard later, since the drive will automatically run at full Gen 4 speed once you move to a compatible platform.

Does PCIe generation affect SSD lifespan or reliability?

No. Drive longevity is determined by the NAND flash type (TLC vs. QLC), the controller’s wear-leveling algorithms, and the TBW (terabytes written) rating. PCIe generation is purely about the interface speed between the drive and your system. A well-made Gen 3 drive can easily outlast a poorly made Gen 4 drive.

Will DirectStorage make PCIe 4.0 essential for gaming?

DirectStorage allows games to load compressed assets directly from your SSD to the GPU, bypassing the CPU decompression bottleneck. In theory, this should make faster SSDs more beneficial for gaming. In practice, early implementations like those in Forspoken and Ratchet & Clank: Rift Apart have shown only modest load time differences between Gen 3 and Gen 4 drives. The technology is still maturing, and it could become more impactful in future titles, but it’s not a reason to upgrade today.

Is it better to get a larger Gen 3 drive or a smaller Gen 4 drive for the same budget?

For most users, go with the larger drive. Running out of storage space is a far more common and frustrating problem than wishing your load times were 0.5 seconds faster. A 2TB Gen 3 drive will serve you better than a 1TB Gen 4 drive in almost every realistic scenario. Capacity matters more than speed once you’ve crossed the NVMe threshold.

This article contains affiliate links. We may earn a small commission at no extra cost to you.

James Kennedy

James Kennedy is a writer and product researcher at Drives Hero with a background in IT administration and consulting. He has hands-on experience with storage, networking, and system performance, and regularly improves and optimizes his home networking setup.