Crucial P1 NVMe SSD Review: QLC Flash Gone Mild (Updated)

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Intel's 660p debuted just a few weeks before the P1 as the first consumer SSD to feature QLC flash. It proved that with enough tweaking and the right pricing, QLC NAND could be competitive despite its lower endurance. The 660p makes the jump to a QLC SSD a bit easier, but the Crucial P1, which features the same components, isn't as convincing.

With synthetic specifications of up to 2/1.75GB/s of sequential read/write throughput, it seems like the Crucial P1 is a faster alternative to the Intel 660p and any SATA-based drive. But while synthetic testing tells you some of the basic capabilities of a drive, real-world application testing tells all. Unfortunately, the Crucial P1 came up short at times during our real-world testing. Times where it matters.

Our goal is to measure the real-world performance that you'll see during daily use. As part of that ethos, we test the drive as a boot volume and fill it to half of its capacity to mirror real-world operating conditions. This process can reduce SSD performance, and the Crucial P1 didn't live up to our expectations under those conditions.

We reached out to Crucial about the lower than expected results. Crucial and Silicon Motion are investigating the issue and a possible fix. In their testing, the 500GB Intel 660p exhibited similar behavior when half full, too. We do not have a 500GB 660p model to verify their findings, but our 1TB Intel 660p did not slow down as much when we filled it to 50% of capacity. We also retested an empty P1 and found that it scored similarly to an empty Intel 660p.

Both Intel and Crucial say their firmware is separate of one another, but with such similar performance between the two drives, we surmise that both are based heavily on Silicon Motion’s firmware.

The P1 scored as low as some SATA SSDs during our PCMark 8 testing, while the Intel 660p was nearly twice as fast. The Crucial P1 also displayed SATA-like performance in SYSmark and lagged the competition in the responsiveness test. Conversely, the P1 installed SYSmark quickly, was agile during our file transfer tests, and was on par with other SSDs during our gaming test. The P1 also displayed stellar sequential write performance during our write saturation test.

Still, pairing this mostly lower application performance with comparatively higher pricing doesn’t make things easy on the P1. Sure, it is faster than a SATA SSD most of the time and is significantly better than any HDD, but competition is brutal in the SSD market.

While the pricing of both the 660p and the P1 have dropped dramatically since launch, the P1 is still slightly more expensive than the Intel 660p. To become competitive, Crucial’s P1 needs a bump up in performance and a better price. If you want faster performance and have room in your budget, the Adata XPG GAMMIX S11, Samsung EVO, and WD Black are better options. The MyDigitalSSD BPX Pro or Corsair Force MP510 are good choices if you're looking for more endurance. Even among low-cost QLC-based NVMe drives specifically, we think the Intel 660p is a better choices if you're on the hunt for a value SSD.

Photo Credits: Tom's Hardware


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Sean Webster
Storage Reviewer

Sean is a Contributing Editor at Tom’s Hardware US, covering storage hardware.

  • rogerdpack2
    Would like some 500GB results
  • Varying size SLC cache? So... this means you can treat QLC cells like SLC with a firmware tweak?
  • gdmaclew
    There is currently no firmware update for this NVMe SSD. I have one.
  • tlmiller76
    I have one of these (1 TB). REALLY sorry that I do. For NVMe, absolute TRASH, even given it's basement price.