This is my motherboard-"Biostar G41D3C Core 2 Quad Intel G41 DDR3 A&V&L MATX Motherboard" Hard Drive -Seagate Barracuda 7200rpm 500 GbComputer Information -CORE 2DUO 2.80 GHZ -RAM 2 GB -Graphic Card -1 GB PAULT NVIDIA
Right now on windows 8.1 64 bit Hard Drive Giving Average write speed- 7 mbps ? but its 7200 rpm. whats the problem ?
13 Answers
A "normal" 7,200-rpm SATA drive can handle only 60-70 IO operations per second to random locations - the time it takes for the disk heads to seek to a track, then for the proper disk sector to pass under the heads limits how many operations per second the disk can do.
If the random IO blocks are small enough - down to individual disk sectors, which are likely 512 bytes for your disk, random IO operations can result in IO rates as low 30 kilobytes per second.
Usually, the "known" hard drives speeds are 70-100MB/s. The issue is that those speeds are valid when the drive reads/write sequential data, but in normal use case (system drive) that's not the case, the system doesn't start to read a big 1GB block sequentially. The OS/System actually read data from different "sectors" in the drive's plates.
e.g., going to read some dll file for the system then going to load Wordpad, and also reading/writing some web page a navigator downloaded.
So the read/write become kind of random (targeting small sparse files on the HDD) that's why the speed will be way lower, because the reading heads will have to "seek" for the targeted sectors, which are physically away from each other (and not one next to the other like with sequential I/O).
That is why hard drive benchmarks have a sequential read/write and also random measures !
SSD drives make this phenomenon less "performance killing" because of the ~0.1ms access time (thanks to flash memory instead of plates in HDD's). But similarly the sequential speeds are also way lower than the random access speeds.
In your case, the (a little bit old hdd) is struggling in random access. That's probably why you experience low read/write speeds.
2You have not problem if that speed is for a large amount of very small files.
If you can hit around 70MB/s for a large file transfer and 7MB/s for very small files, it's perfectly normal for that drive.
If however you have 7MB/s on a large file, then you have a technical problem with the HDD.
