Everyone wants to get the best performance for their PC that they can afford, and NVMe SSDs are a tempting—and easy—way to improve how quickly your PC responds. Unfortunately, the real world isn’t a benchmark, and the actual performance gains you get aren’t as simple as the speeds advertised on the drives suggest.
This is what you need to know to avoid overspending on storage.
What do PCIe standards mean for NVMe storage?
Most NVMe drives you see today use PCIe to connect to your motherboard, and as a result, the speed of the PCIe interface limits the maximum speed of your drive.
Some solid state drives use the SATA interface and the M.2 connection, which makes them easy to confuse with PCIe NVMe drives that also use the M.2 connector.
M.2 SATA drives are limited to SATA speeds—about half a gigabyte per second (GB/s)—and you should avoid them unless you very specifically need one. They’re worse than a PCIe NVMe SSD in pretty much every way, and they’re not any less expensive these days.
Each new PCIe generation doubles the amount of bandwidth available per lane. For example, a PCIe 3.0 interface with 4 lanes (written x4) will have a maximum bandwidth of 1GB/s per lane, giving you a total bandwidth of 4GB/s. A PCIe 4.0 x4 interface will have a maximum bandwidth of 8GB/s, and a PCIe 5.0 x4 interface will have a maximum bandwidth of 16GB/s.
Related
What Is PCIe 5.0, and Why Does It Matter?
More bandwidth than you can shake an Ethernet cable at!
In raw benchmarks that measure the read and write speeds of PCIe NVMe drives, they usually get pretty close to the theoretical maximum. For example, Samsung’s P9100 Pro, which is a PCIe 5.0 x4 drive, achieves real-world read and write speeds around 14GB/s.
So, you’d assume that you always want to buy the fastest possible drive you can, right? Like with most things, real world applications muddy the waters.
Real-world limitations make buying PCIe 5.0 drives complicated
It is great to be able to say that PCIe 5.0 is twice as fast as PCIe 4.0 and four times faster than PCIe 3.0, but that benefit largely disappears in many real-world applications, especially gaming.
PCIe generation doesn’t matter much for gaming
Our own benchmarks have shown that there is only a tiny difference between the performance of a PCIe 3.0 NVMe drive and a PCIe 5.0 drive in gaming. If you’re talking about FPS, the difference is basically nonexistent.
You’d also naturally assume that the loading time on a PCIe 5.0 drive would be half of a PCIe 4.0 drive and a quarter of a PCIe 3.0 drive, but that isn’t the case either—in most games, there isn’t much of a difference at all.
The problem here isn’t the drives themselves. Benchmarks can easily verify that they read and write at the speeds they should. The problem is that the overwhelming majority of games today don’t, and probably can’t, properly make use of the extraordinary speeds available with the fastest NVMe drives.
The disappointing gaming performance of NVMe drives is going to change over time, especially as standards like DirectStorage become the norm, as game engines are optimized for the speeds offered by NVMe drives, and as developers learn how to squeeze the best performance possible out of them. However, if you’re building a PC mostly for gaming, you probably don’t need to spring for the fastest PCIe 5.0 drive available—you’re better off spending that money elsewhere.
PCIe 5.0 is great for productivity
While PCIe 5.0 and PCIe 4.0 drives don’t really deliver over their 3.0 counterparts for gaming, the same isn’t true of most creative applications. That includes local AI applications, photo and video editing, 3D modeling, and even some CAD applications.
Those sorts of programs and workloads often involve moving, importing, editing, and then exporting large files, which is exactly where the ultra-fast PCIe NVME drives really shine. Uncompressed RAW 4K video files can eat up to 10GB per minute of footage. If you’re manipulating a few hours worth of footage, the difference between the 4GB/s you get from PCIe 3.0 and 16GB/s on PCIe 5.0 is going to be very noticeable.
Only buy SSDs that you can actually use
PCIe 5.0 was introduced in 2019, but it took years for motherboards and CPUs that feature it to appear on the market. As a result, there are a ton of very capable PCs out there today that lack PCIe 5.0 entirely. If you’re looking to upgrade the storage in your PC, it pays to know which PCIe standard you have, since PCIe 5.0 drives are usually anywhere between 20% and 40% more expensive than their PCIe 4.0 counterparts on a per-gigabyte basis.
On the high end, you can get PCIe Gen 5 SSDs that have a maximum bandwidth of about 14GB/s. If you plugged that same drive into a PCIe 4.0 x4 port, you’d instantly be limited to 8GB/s at best, only 40% of the drive’s performance. You could pay more for absolutely nothing.
The manual for your motherboard (or prebuilt) will tell you which is available to you.
Even if you just built your PC recently, you need to be a little careful. The current generation of motherboards usually have a mix of PCIe 5.0 and PCIe 4.0 ports available, rather than exclusively opting for PCIe 5.0. That means you need to know how your PCIe slots are divided up when picking out your SSDs.
Typically, a motherboard that has PCIe 5.0 will have enough lanes to run one full x16 port and one x4 port, which ensures you can run a GPU at full speed and at least one PCIe 5.0 NVMe at full speed. If you’re going to use more than one NVMe SSD, odds are that the second one will only be able to run at PCIe 4.0 speeds.
Given that the cost difference between PCIe 4.0 SSDs and PCIe 5.0 SSDs can sometimes be hundreds of dollars, it always makes sense to consider how you’re going to use it and whether it can provide any benefit. After all, when you’re talking about that much money you could buy up your GPU, get a nicer monitor, or deck our your peripherals instead.
Credit: Western Digital
Storage capacity
2TB
Hardware Interface
PCIe Gen4x4
Compatible Devices
PS5, PC
Brand
Western Digital
Dimensions
80.01 x 22.1 x 2.29 mm
Weight
7.5 g
The WD_BLACK SN850X is even faster than the SN850 it replaces, making it an even better option for your PlayStation 5. The Sony-recommended heat sink helps ensure that your drive will last just as long as your PS5 does.
