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

Mixed Random Performance

Our test of mixed random reads and writes covers mixes varying from pure reads to pure writes at 10% increments. Each mix is tested for up to 1 minute or 32GB of data transferred. The test is conducted with a queue depth of 4, and is limited to a 64GB span of the drive. In between each mix, the drive is given idle time of up to one minute so that the overall duty cycle is 50%.

The Team T-Force Cardea has average performance on the mixed random I/O test. It's about the same speed as Samsung's 850 PRO SATA SSD, and is substantially outperformed by some of the larger Phison E7 drives and the Toshiba OCZ RD400. The Samsung 960 EVO does poorly here, with only 75% of the performance overall compared to the T-Force Cardea.

The power efficiency of the T-Force Cardea isn't great; the SATA SSDs that come close to its performance level do so while consuming much less power. While the T-Force Cardea was 32% faster than the Samsung 960 EVO, the Samsung closes the gap a bit on efficiency, leaving the T-Force Cardea with only an 11% efficiency advantage.

Team T-Force Cardea 240GBSamsung 950 PRO 256GBSamsung 960 EVO 250GBPatriot Hellfire 480GBOCZ RD400 256GBIntel SSD 750 400GBCorsair Neutron NX500 400GBZotac SONIX 480GBSamsung 850 EVO 250GBSamsung 850 PRO 256GBPNY CS2211 240GB

The performance of the T-Force Cardea increases slowly across most of the test, until the write volume is high enough to trigger garbage collection. The larger Phison E7 drives never reach that threshold and instead show a spike in performance at the end of the test when the workload is pure writes that can be cached and combined.

The Samsung 960 EVO starts out with slightly higher performance on the random read side of the test, but degrades as the proportion of writes increases through the first half of the test, before increasing at the end and surpassing the T-Force Cardea when it is busy doing background garbage collection.

Mixed Sequential Performance

Our test of mixed sequential reads and writes differs from the mixed random I/O test by performing 128kB sequential accesses rather than 4kB accesses at random locations, and the sequential test is conducted at queue depth 1. The range of mixes tested is the same, and the timing and limits on data transfers are also the same as above.

The top performers on the mixed sequential I/O test are both older NVMe drives: the Samsung 950 PRO and Intel SSD 750. Several of the Phison E7 drives and the Samsung 960 EVO and 850 PRO are all tied for average speed, while the Zotac SONIX and OCZ RD400 are 100MB/s faster.

The Team T-Force Cardea has much better performance per Watt than the other two Phison E7 SSDs that performed the same, and is almost as efficient as the Zotac SONIX that performed much better. Among currently-available NVMe SSDs, the Toshiba OCZ RD400 seems to the best combination of performance and power efficiency on this test.

Team T-Force Cardea 240GBSamsung 950 PRO 256GBSamsung 960 EVO 250GBPatriot Hellfire 480GBOCZ RD400 256GBIntel SSD 750 400GBCorsair Neutron NX500 400GBZotac SONIX 480GBSamsung 850 EVO 250GBSamsung 850 PRO 256GBPNY CS2211 240GB

The T-Force Cardea's performance drops slightly early in the test, but mostly shows increased performance as the proportion of writes increases. There's no sign of the total write volume being enough to force the drive to perform garbage collection outside of the idle periods between sub-tests. The Samsung 960 EVO's performance is almost a mirror of the T-Force Cardea's, with much better performance on the read-heavy half of the test than the write-heavy second half. Samsung's SATA drives are also better on the read-heavy portions. So while several drives are tied for overall average performance, the Samsung drives perform better on the kinds of I/O that consumer workloads are mostly comprised of.