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Full user review
"The best free real-world test?"
Easy to use.
Measures performance on small, medium and large files.
Measures both Read and Write performance.
Closer to real-world performance than either ATTO or free HD Tune.
Generalized performance measurement rather than specific for your needs such as Home Theater PC, Productivity (MS Office, etc.) or Gaming.
Manufacturers of SSDs and regular hard disk drives (HDD for short) want to show the performance of their product in the most favorable way so they measure it under ideal conditions (ATTO benchmark) which tell you little about its true performance, rather like the MegaPixel (MP) ratings of digital cameras. These ideal conditions involve data or files that can be easily "compressed" whereas, on your computer, much of your data and files cannot be compressed, thus making your SSD or HDD work harder and return lower number results. How your chosen drive handles small file sizes of incompressible data (such as 4Kb to 64Kb) throughout the day is most relevant, but medium & large incompressible performance is useful for 3D gamers and for video & photo editing or copying big files from one drive to another. To see professional measurements of these real-world scenarios you can check out the combined "storagemark" results for many different drives at storagereviewdotcom. But for free and relatively quick measurement at home you'll be hard pressed to find a better test than CrystalDiskMark !! Things to remember when testing:
1. When the drive is nearly empty you get the best test result.
2. Don't have a bunch of other programs running while you're testing.
3. If the drive is an SSD, be sure to "Log off" (not Shutdown) for several hours before testing. SSDs have their own software which tunes up the performance when the computer is idle for awhile.
4. Restart your computer before testing.
6 year-old to 10 year-old drives will probably measure very slow compared to 2 year-old and newer drives, so replacing an old hard drive can make an older computer run everything noticeably faster, especially if you install an SSD instead of a regular HDD (maybe keep the old drive for storing all your photos, documents, videos, music, etc.).