The Team Group T-Force Cardea (240GB) SSD Review: Grace Under Write Pressure

Conclusion

Modern 3D NAND tends to be manufactured with a high capacity per die, which makes it difficult to make a high-performance low-capacity SSD. The Team T-Force Cardea avoids that problem by using Toshiba's 15nm planar MLC NAND. The result is a drive that handles heavy workloads quite well without the performance drops that are typical of TLC SSDs. The Phison E7 SSD controller platform used by the T-Force Cardea helps keep costs much lower than most other MLC-based drives, though the heatsink prevents it from being the cheapest Phison E7 drive on the market.

The most important competitor at the low end of the capacity range is Samsung's 960 EVO 250GB. The MLC-based 960 PRO isn't available at capacities below 512GB, and the previous generation 256GB 950 PRO is out of production. Thanks to the strength of Samsung's Polaris controller, the 250GB 960 EVO manages to be the fastest drive in its class for light workloads. But when heavier workloads with a high volume of writes are involved, the T-Force Cardea comes out ahead.

We haven't seen any strong evidence that the heatsink helps the T-Force Cardea under ordinary conditions. In fact, we often see performance degrade as a test continues and the accumulated volume of writes forces the drive to continue performing garbage collection beyond the idle time our test protocol provides. Larger SSDs and many competing 240GB-class SSDs seem to be able to wrap up their garbage collection more quickly, leading to more consistent sustained performance. But this shortcoming of the T-Force Cardea is only really noticeable on our synthetic benchmarks; even our most intense tests of real-world I/O patterns have it clearly outperforming SATA SSDs and most cheaper NVMe SSDs.

The most significant performance weakness we spotted during our testing is with sequential reads. Samsung's NVMe SSDs are several times faster at queue depth 1. The gap narrows at higher queue depths, but all of the Phison E7 SSDs are still at a disadvantage here.

Current pricing has the 240GB T-Force Cardea well above the Samsung 960 EVO, and just below it at the half-TB capacity class. For most users, the 960 EVO's performance profile will be a better fit, making the 960 EVO the better buy. For a particularly heavy workload at, the T-Force Cardea may be a better choice than the 250GB 960 EVO. But since it doesn't appear that the heatsink matters in ordinary use, most users can save even more money by going with a cheaper Phison E7 drive like the MyDigitalSSD BPX.

In an upcoming review, we will more thoroughly explore the thermal limits of M.2 SSDs, including when positioned near a hot-running graphics card. That may reveal the large heatsink on the Team T-Force Cardea to occasionally be a significant advantage.