How Much Faster Games Load on an SSD Than a Hard Drive

The load time argument was settled years ago, and if that were the only difference a hard drive would still be a perfectly reasonable place to keep a large library. It isn’t the only difference any more, and the reason is worth understanding before you decide where to install things.

The numbers, roughly

Real figures vary by title, but the shape is consistent across modern games:

• A mechanical hard drive at 7200rpm manages around 120 to 160 MB/s sustained, and critically, terrible random access, because a physical head has to move.
• A SATA SSD manages around 550 MB/s, with random access effectively instant.
• NVMe Gen 3 runs to roughly 3,500 MB/s.
• NVMe Gen 4 runs to roughly 7,000 MB/s.

In practice, a large open world game that takes 90 seconds to load from a hard drive typically loads in 20 to 25 seconds from a SATA SSD. Moving from SATA to NVMe often only saves another few seconds, because at that point the bottleneck has moved to the CPU decompressing assets rather than the drive supplying them.

That last point is the one people get wrong. The jump from HDD to any SSD is enormous. The jump from a decent SATA SSD to a fast NVMe drive is modest for most games, and paying a premium for Gen 5 speeds won’t make your games load meaningfully faster.

The thing that changed

Loading screens are the visible problem. Asset streaming is the real one.

Games built for the current console generation assume the storage underneath them is fast, because both consoles ship with NVMe drives and custom decompression hardware. Rather than loading a level once and holding it in memory, these games continuously pull in textures, geometry and audio as you move through the world.

On a hard drive that assumption breaks. The symptoms aren’t longer loading screens. They are:

• Textures appearing at low resolution and popping in a second or two later
• Hitching when you turn a corner or move quickly through an area
• Traversal stutter in open world games, particularly when driving or flying
• In severe cases, geometry that hasn’t finished loading being briefly invisible

Several recent releases have listed an SSD as a minimum requirement rather than a recommendation, and that isn’t marketing. It reflects the fact that the streaming system was never designed to tolerate the latency of a mechanical drive.

Where a hard drive still makes sense

Cold storage. Games you aren’t currently playing, older titles built before streaming architectures, and anything from before roughly 2018 will run perfectly well from a mechanical drive. Per terabyte it’s still substantially cheaper, and a large library doesn’t need to sit on fast storage in its entirety.

A sensible split is a 1TB or 2TB NVMe drive holding whatever you’re actively playing, with a larger mechanical drive underneath as the archive. Steam supports multiple library folders and will let you move an installed game between drives in a few clicks without redownloading it, which makes this arrangement much less tedious than it sounds.

One warning about capacity

SSDs slow down noticeably when nearly full, because the controller has less free space to work with. Keeping around 10 to 15% free is worth more than the extra couple of games you could squeeze on. A 90% full SSD can perform worse in sustained writes than a healthy one at half capacity.

This matters more than it used to, now that individual installs regularly pass 100GB and updates rewrite large chunks of them.