The Samsung 840 is the budget version of the 840 Pro, the main difference between the hardware on the two drives is the type of flash memory used. The cheaper 840 uses TLC NAND which is cheaper than the MLC found in the Pro version of this drive. The performance hit as a result of the cheaper TLC memory is approximately 30%. The 840 delvers both average real world speeds (435 MB/s) and average enterprise speeds (AS-SSD Total Score 920). The relative weak spots in this drives performance profile are its write ability, where it scores just 254 MB/s in the sequential write test. The upside to the lost performance over the Pro version is a significant reduction in price which leaves this drive an average value for money proposition at its current price of £135. There are, however, better value drives to be had elsewhere including Samsungs own newly released EVO which effectively supersedes the 840. [Aug '13SSDrivePro]
The 250GB Samsung 850 Evo has a similar architecture to its hugely successful predecessor, the 840 Evo. Both drives are TLC based but the 850 uses 3D V-NAND as opposed to regular NAND. Both drives also feature a Turbowrite cache (TWC) which buffers up to 3GB of writes. The TWC enables high burst write speeds but when the cache exhausts write speeds drop to 300 MB/s. Comparing the 850 and 840 Evos shows that effective speed, has improved by 11% and the warranty has been extended from three to five years but prices are also up by 11%. The 850 Evo does put in superb benchmarks (second only to the 850 Pro) but these are only valid within the TWC. At current price levels the 850 Evo struggles to compete with the value leaders. [Dec '14SSDrivePro]
Welcome to our 2.5" and M.2 SSD comparison. We calculate effective speed for both SATA and NVMe drives based on real world performance then adjust by current prices per GB to yield a value for money rating. Our calculated values are checked against thousands of individual user ratings. The customizable table below combines these factors to bring you the definitive list of top SSDs. [SSDrivePro]
Welcome to our PC speed test tool. UserBenchmark will test your PC and compare the results to other users with the same components. You can quickly size up your PC, identify hardware problems and explore the best value for money upgrades.