As you likely know, while manufacturers claim impressive peak I/O performance out of the box, this performance can diminish over time. Unlike a conventional hard drive, any write operation made to an SSD is a two-step process: a data block must be erased and then written to. Obviously if the drive is new and unused there will be nothing to erase and therefore the first step can be bypassed, but this only happens once unless the drive is trimmed. Considering this, we’ll test how much performance you can expect to lose from each SSD over time. We’ll examine all drives in their clean unused state, and then run the HD Tach full benchmark several times to fill the drive. This simulates heavy usage and clearly indicates how performance will be affected after normal long-term use.

Most drives support the TRIM function, which is meant to counteract these negative effects. Test System Specs

Intel Core i7-4770K (LGA1150) x2 4GB DDR3-1600 G.Skill (CAS 8-8-8-20) Asrock Z97 Extreme6 (Intel Z97) Silverstone Strider Series (700w) Western Digital Black 4TB Western Digital Velociraptor 1TB Plextor M6e 256GB Plextor M6S 256GB Samsung SSD 850 Pro 512GB Samsung SSD 840 Pro 512GB Samsung SSD 840 Evo 1TB SanDisk Extreme Pro 512GB SanDisk Extreme II 240GB OCZ RevoDrive 350 480GB OCZ Vector 150 240GB OCZ Vertex 460 256GB Intel SSD 520 Series 240GB Gainward GeForce GTX 780 (3072MB)

Microsoft Windows 8.1 Pro (64-bit) Nvidia Forceware 340.43