HDD vs SSD

Hard Disk Drive vs Solid State Drive Characteristic Hard Disk Drive (HDD) Solid State Drive (SSD) Sensitive to Magnets Magnets will alter or destroy data Magnets have no effect on data Power Consumption 7 Watt average 2 Watt average Time to Spin Up Up to 2 seconds before HDD can read/write to drive Instantaneous, able to read/write immediately Read Speed (SATA) Roughly 100MB/s, can very depending on level of fragmentation 250 MB/s Write Speed (SATA) 50-70 MB/s, can very depending on level of fragmentation. Up to 118 MB/s on HDD's such as the WD Velociraptor. 200-250MB/s. Lifespan May fail due to vibrations or impact, usual MTBF of 1,500,000 hours (171 years) No finite number of writes MTBF of 2,000,000 hours, AKA 228 years. Or about 40 years of non-stop writing due to write cycle limits Encryption HDD's can overwrite encrypted data right on top of the old data SSD's need a secure erase feature or total partition encryption. (Can not overwrite data, data must be erased first) Cost HDD's cost about $0.11 USD per gigabyte as of 3/17/2011 Solid state drives cost about $1.80 USD per gigabyte as of 3/17/2011 Sound HDD's typically make noticable sound during read/write and spin up times. Solid state drives have no moving parts and make no sound. Heat Very little heat produced, but still 3 times more heat than SSD's. Only produce about 1/3 the amount of heat of an HDD. Sensitivity to Shock Very sensitive, hard disk drive heads and disks may break due to shock or vibration Solid state drives have no moving parts and are very resistant to shock and vibration Fragmentation Level of fragmentation of an HDD will significantly reduce read/write speeds No need to defragment solid state drives due to not having any read/write heads to find the data Appearance High Performance Example Western Digital Caviar Black 640GB 3.5" SATA 3.0Gb/s Internal Hard Drive -Bare Drive OCZ Vertex 2 OCZSSD2-2VTXE120G 2.5" MLC Internal Solid State Drive (SSD)