Speed of Hard Drive Write and Read Speed 7200rpm

7200 RPM is the rotational speed, it doesn't have any direct relationship to MB/ s throughput. That depends on -the hard drive (its design, areal density, seek performance, caching performanc e), -the operating system, -the size of the platters, -how full the drive is, -what interface the drive is using -the type of data being read and written. Neither does the cache size directly relate to MB/s In general, a 7200 RPM drive will have higher throughput than a 5400 RPM drive. A desktop (3.5") drive will have higher throughput than a laptop (2.5") drive at the same rotational speed. 12 MB/s write and 27 MB/s read is pathetic performance for a hard drive, It is a verage- to decent-performance for a USB memory stick. A typical hard drive is capable of up to 80 - 100 MB/s throughput when new. Driv es slow down as they fill up. The fastest hard drives can hit about 120 MB/s. RA ID arrays can get up tp 200 - 400 Mb/s (yes, I know that SATA-II and SATA-III in terfaces are capable of up to 3.0 (300 MB/s) and 6.0 Gb/s (600 MB/s) but that is the *Interface* maximum, not the actual drive performance) A SSD drive can manage up to 275 Mb/s The USB 2,0 interface limits the performance of any storage device to about 30 40 MB/s Firewire 400 is faster, Firewire 800 faster than that (about 80 MB/s), eSATA at 150 MB/s is the fastest common external interface, it can handle pretty much the full output of any single hard drive. Keep in mind that the rates quoted are maximum rates -- average real-world trans fer rates are affected by many factors and will be lower.