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ATTO Disk Benchmark is perhaps one of the oldest benchmarks going and is definitely the main staple for manufacturer performance specifications. ATTO uses RAW or compressible data and, for our benchmarks, we use a set length of 256mb and test both the read and write performance of various transfer sizes ranging from 0.5 to 8192kb. Manufacturers prefer this method of testing as it deals with raw (compressible) data rather than random (includes incompressible data) which, although more realistic, results in lower performance results.
A bit confusing perhaps… The XPG Spectrix S40G reaches listed read speeds of 3.5GB/s no problem but, at least this software, has us stalled at 1.8GB/s for read performance. We tested same in our Z370, X299 and newest X570 systems just to ensure what we were seeing was correct.
CRYSTAL DISK BENCHMARK VER. 7.0.0 x64
Crystal Disk Benchmark is used to measure read and write performance through sampling of random data which is, for the most part, incompressible. Performance is virtually identical, regardless of data sample so we have included only that using random data samples.
THROUGHPUT
IOPS
Crystal Diskmark performance appears quite a bit better, write throughput still being just a bit short, however. Conversely, both read and write IOPS are better than listed specs.
The toughest benchmark available for solid state drives is AS SSD as it relies solely on incompressible data samples when testing performance. For the most part, AS SSD tests can be considered the ‘worst case scenario’ in obtaining data transfer speeds and many enthusiasts like AS SSD for their needs. Transfer speeds are displayed on the left with IOPS results on the right.The AS SSD results aren’t as appealing as we might like to see but do get a first look at read and write IOPS which appear to be in the general ball park of listed specs.
AS SSD displays what we might expect for throughput read and even IOPS, however, the high sequential write performance should be much higher.