When I first saw the price for the Silicon Power PC60 I wondered how they were doing it as the NVMe drive and USB bridge must cost more than that. After disassembly, the mystery is solved. While other vendors put NVMe drives in their USB 3.1 enclosures, Silicon Power chose a SATA-based drive, which of course has performance implications, but is the secret sauce for the unbelievably low price point.

Visually, the Silicon Power PC60 looks good; the clean black design will fit in everywhere. A metal casing would have been nice, but I can understand how pricing wouldn't allow it. It's great that Silicon Power included a cable with the enclosure. It's USB Type-A to USB-C, which makes sense with the drive's positioning—mostly for owners of older computers, which might not have USB-C yet. A slightly better approach would be to bundle a standard USB-C to USB-C cable and include a small USB-C to Type-A adapter, so everyone is covered, which shouldn't cost much more.

Our performance testing shows good numbers for random read IO that basically match what much more expensive, portable SSDs offer. Sequential reads are a bit lower, but still close to 500 MB/s, which isn't that far from the 700–800 MB/s more premium external SSDs achieve. The PC60's biggest weakness is write performance, especially random write. With random access throughput of just 2,730 IOPS, the PC60 offers roughly 1/10th the speed of other portable SSDs. The underlying reason for that is the lack of a DRAM cache chip.

DRAM on an SSD is used as fast temporary storage for the drive's internal mapping tables, which translate between physical disk addresses (as seen by the OS) and the actual location of where the data is stored in the flash chips: "which chip, at which location." Using DRAM has a speed advantage as it operates much faster than flash, but it's a cost/performance trade off. Silicon Power opted for the cost reduction, as that's the whole philosophy behind the PC60. If you copy large files, like ISOs or movies, the impact of low random IO performance will be negligible. Use it as a data drive for applications running on your system, as a Windows-to-Go device, or to copy lots of small files to the SSD and performance will be severely impacted. People tend to buy portable SSDs as opposed to just high-capacity USB flash drives in hopes of higher random-access performance for use in Windows-to-Go devices in BYOD work environments. If you count yourself among them, you're better off spending a little extra money on a portable SSD that can take an NVMe drive internally, such as the Crucial X8, which not only uses an NVMe drive, but also passes on the benefits of UASP.

If you plan on writing huge amounts of data in each session, the PC60 might not be the best choice, either. It comes with an SLC cache of 32 GB, which is rather small for an external enclosure that might see tons of data written to it for transport to another system. Also, once the 32 GB pseudo-SLC cache is exhausted, write rates drop dramatically to only 85 MB/s—lower than most HDDs. Be aware of this, though it's not a huge deal for many use cases—stay below that 32 GB limit and you'll be fine. If you expect to fill up a TB in a few minutes for backup/disk imaging purposes, then look elsewhere. Once you give the drive some room to breathe, it will flush the SLC cache to TLC in the background, which quickly restores full write speeds.

Priced at just $88 for the 1 TB version, the Silicon Power PC60 is incredibly affordable. I checked on Newegg, and there's not a single 2.5" SATA SSD at that price point. Here I am again wondering how Silicon Power can achieve such a price. If you need the absolutely cheapest SSD for read-heavy workloads, I can even imagine it making sense to buy the PC60 to install the 2.5" SATA SSD in your case and stash away the USB-to-SATA adapter. This could also be a use case for this PC60 in a couple of years, once you've replaced it with a different portable SSD; just plop out the 2.5" SATA SSD and put it in an older system to upgrade its storage, or replace an aging HDD for a free performance upgrade.

If you need a high-performance portable SSD, you should be ready to spend around $130 and above on a drive that is truly based on an NVMe SSD internally—like the ADATA SE800. The Crucial X8 or HP P700 are even faster, but more expensive, too. For many users, especially if you are patient, that might be too much of a price increase, so I think the PC60 definitely adds an interesting option to the market.