Journal · Storage & Memory
How fast is a PCIe Gen4 portable SSD, really?
Short answer
A PCIe Gen4 portable SSD reads at up to 7,400 MB/s — about 50× faster than an external hard drive and 13× faster than an older SATA SSD. In practice: an hour of 4K footage copies in under a minute. The catch is sustained speed, which depends on the enclosure keeping the drive cool.
The number, translated into real jobs
7,400 MB/s is a sequential read figure — how fast the drive streams one large file. A 60GB hour of 4K footage moves in well under a minute; a 500GB project archive copies before the kettle boils. A typical external hard drive manages ~150 MB/s and an older SATA-based portable SSD tops out near 550 MB/s. Gen4 NVMe isn't an increment — it's a different category.
Read vs write vs random
- Sequential write — what you feel offloading camera cards or running backups. Good Gen4 drives write at 6,000+ MB/s.
- Random performance — thousands of small files (a photo library, a code repo) behave differently from one big video; NVMe's advantage here over hard drives is even larger than the headline suggests.
The spec nobody prints: sustained speed
Every SSD has a fast cache; once a long transfer exhausts it, speed depends on the controller and on heat. A drive in a plastic shell can hit its rated speed for thirty seconds, then throttle hard as the chips warm — and in a UAE summer that ceiling arrives sooner. An aluminium body acts as a heatsink, so the tenth minute of a transfer looks like the first. When comparing drives, ask what it sustains, not what it peaks.
One cable can halve your speed
A Gen4 drive on a cheap cable silently negotiates down to a fraction of its speed. Use the rated cable it shipped with or a certified USB4/Thunderbolt cable, plugged into your machine's fastest port — not a hub's passthrough.
Frequently asked questions
Can I edit 4K video directly off a portable SSD?
Yes — at Gen4 speeds, editing 4K (and most 6K proxies) straight off the drive is realistic, provided the enclosure sustains its speed and you're on a USB4/Thunderbolt port.
Does a Gen4 SSD work with older USB ports?
Yes, it's backwards compatible — it will simply run at the older port's maximum speed. You lose speed, never compatibility.
Is 512GB, 1TB or 2TB the right size?
512GB suits documents and photo libraries; 1TB is the sweet spot for creators shooting 4K regularly; 2TB pays off for video professionals and game libraries. Whatever you choose, keep a second copy — speed is a feature, a backup is a policy.
Storage that keeps its promises
Gaatly NVMe drives — aluminium shells, sustained Gen4 speed, 2-year warranty.