The Team Group Cardea Zero Z44Q is one of only a few QLC-based PCIe 4.0 SSDs on the market. Actually, there are only two others: the Corsair MP600 Core and Sabrent Rocket Q4. We reviewed the latter just a few weeks ago, and it's basically the same drive as the Cardea Zero, down to some of the quality-control stickers on the SSD. The PCIe Gen 4 interface promises twice the throughput of Gen 3, so SSD makers exploring all possible options is only natural. Internally, the Cardea Zero Z44Q is based on the combination of 96-layer QLC flash from Micron paired with the Phison E16 controller, plus 2 GB of DRAM cache.

Synthetic numbers of the Team Group Cardea Zero Z44Q are very impressive. Especially random IO, both read and write, and sequential transfers are mighty impressive. If our review stopped here, we'd conclude that the Z44Q is a high-performing Gen 4 SSD that offers performance rivaling the latest Gen 4 TLC drives at much better pricing.

Our real-life testing suite goes beyond synthetics and runs the actual applications at 80% disk full, which is a more realistic scenario than a completely empty drive running a synthetic test. Real-life benchmarks are much harder to optimize for, too. Here, the Z44Q shows much weaker numbers that are surprisingly low. When averaged over all our tests, the SSD matches PCIe 3.0 mid-range drives like the Kingston A2000 and Samsung 970 EVO. High-end Gen 3 drives like the ADATA SX8200 Pro, Kingston KC2000, HP EX950, and Hynix Gold P31 are between 6 and 9% faster—not that much, but still significant. On the other hand, if you know your workload consists of lots of large transfers, like when copying huge files, the Z44Q will definitely shine because of the PCIe 4.0 interface. For example, in our ISO file copy test, the Team Group SSD is the fifth-fastest drive we ever tested—pretty nice. Looking back at averages, the Samsung 980 Pro and WD Black SN850 are the fastest PCIe 4.0 drives, being up to 12% faster at much higher pricing.

Sequential write performance of the Cardea Zero Z44Q starts out fantastic. While writing to pseudo-SLC cache, the transfers complete at impressive 3.5 GB/s and are sustained for very long. Actually, the SSD will fill its whole capacity with SLC data first and only then start writing to QLC directly. In this state, write speeds are down by more than 90%, reaching around 250 MB/s only. Of course, momentarily stopping the write activity will have the SLC cache free up capacity immediately, so full write rates are available as soon as you give the drive a moment to settle down.

If you feel you need better cooling for your SSD, Team Group has you covered. They bundle two cooling solutions with the drive for whether you have the space available (desktop PC) or not (laptop). While the laptop cooling solution comes with claims of "graphene," which has almost magical thermal properties, I found no evidence of this being graphene, but that doesn't mean it's not working. The foil actually results in a pretty decent improvement for how simple a design it is. While thermal throttling still happened in our testing, throttled write speed went up considerably, to 2.5 GB/s compared to 1.8 GB/s for the uncooled drive. Adding the large heatsink only marginally improves transfer rates, to 2.6 GB/s, but delays throttling by an additional three minutes, which is an eternity considering how much data you can write every second. Compared to the Sabrent Rocket Q4 heatsink design, the Z44Q heatsink is a bit weaker mostly because the Sabrent heatsink has more mass with which to soak up more heat before throttling.

Priced at $310 for the tested 2 TB version, the Cardea Zero Z44Q isn't exactly cheap. Now, if you compare against PCIe 4.0 TLC drives, $310 is a bargain, of course. The Samsung 980 Pro 2 TB and WD Black SN850 are both $400. The Corsair MP600 Pro is even $420—no idea why it's so expensive. The problem is that these drives are considerably faster than the Cardea Zero and built using TLC flash, which has better write speeds and longer endurance. Strong competition comes from the high-end PCIe 3.0 drives, too, as they are faster than the Team Group drive and more affordable. For example, the HP EX950 2 TB and Kingston KC2500 are $290, and the ADATA SX8200 Pro 2 TB is only $250.