The ADATA Premier SP550 SSD Review: A Second Look At Silicon Motion's SM2256 Controller

ATTO

ATTO's Disk Benchmark is a quick and easy freeware tool to measure drive performance across various transfer sizes.

ADATA Premier SP550 120GBADATA Premier SP550 240GBADATA Premier SP550 480GBADATA XPG SX930 120GBADATA XPG SX930 240GBADATA XPG SX930 480GBCorsair Neutron XT 480GBCrucial BX100 120GBCrucial BX100 250GBCrucial BX100 500GBCrucial BX100 1TBCrucial BX200 480GBCrucial BX200 960GBCrucial MX100 512GBCrucial MX200 250GBCrucial MX200 500GBCrucial MX200 1TBOCZ Trion 100 240GBOCZ Trion 100 480GBOCZ Trion 100 960GBOCZ Vector 180 240GBOCZ Vector 180 480GBOCZ Vector 180 960GBPlextor M6V 256GBSamsung 850 EVO M.2 120GBSamsung 850 EVO mSATA 250GBSamsung 850 EVO M.2 500GBSamsung 850 EVO mSATA 1TBSamsung 850 EVO 1TBSamsung SSD 850 Pro 512GBSamsung 850 Pro 2TBSanDisk Extreme Pro 480GBSanDisk Ultra II 240GBToshiba Q300 480GB

Most drives should maintain very steady performance once they hit their limit.  The uneven performance on the second half of the test is a sign that the SP550 has some performance problems that deserve investigation with the rest of our benchmarks. That said, the graphs aren't as inconsistent as the Crucial BX200's, where it was obvious that it had severe issues.

AS-SSD

AS-SSD is another quick and free benchmark tool. It uses incompressible data for all of its tests, making it an easy way to keep an eye on which drives are relying on transparent data compression. The short duration of the test makes it a decent indicator of peak drive performance.

The AS-SSD test is short enough that the SP550 doesn't run out of SLC cache headroom and into trouble, and its peak performance is fine for a low-end drive.

Idle Power Consumption

Since the ATSB tests based on real-world usage cut idle times short to 25ms, their power consumption scores paint an inaccurate picture of the relative suitability of drives for mobile use. During real-world client use, a solid state drive will spend far more time idle than actively processing commands. Our testbed doesn't support the deepest DevSlp power saving mode that SATA drives can implement, but we can measure the power usage in the intermediate slumber state where both the host and device ends of the SATA link enter a low-power state and the drive is free to engage its internal power savings measures.

We also report the drive's idle power consumption while the SATA link is active and not in any power saving state. Drives are required to be able to wake from the slumber state in under 10 milliseconds, but that still leaves plenty of room for them to add latency to a burst of I/O. Because of this, many desktops default to either not using SATA Aggressive Link Power Management (ALPM) at all or to only enable it partially without making use of the device-initiated power management (DIPM) capability. Additionally, SATA Hot-Swap is incompatible with the use of DIPM, so our SSD testbed usually has DIPM turned off during performance testing.

When aggressive link power measurement is disabled, the SP550 doesn't do a particularly good job of saving power, and is much worse than its Phison-based competition.

However when the SP550's power saving modes can kick in, Silicon Motion's efficiency shines and the idle power drops to near the limit of our meter's resolution. The Phison-based TLC drives fall slightly behind and the drives that don't implement device-initiated power management stand out.