SATA3 6Gb/s HDD vs SSD

Question

So I know a SATA3 handles a maximum speed of about 750MB. But when comparing this HDD and this SSD, what would be the difference in terms of read/write speed. Won't they both be using the SATA3 busing and having a maximum speed of 750MB? If I wanted to choose a drive that gives me the best read/write speed, which one should I go for, or are they both relatively the same?

Solution 1

The SSD is much faster. The HDD has 10000rpm but is still slower.

// Edit. Add content of my comment to the answer:

Because a HDD is limited by it platters and spindle. Moving the head to the right position takes some time. SSDs don't have this. SSD can be read much faster because it doesn't have an mechanic parts. The data are read from Flash modules. Here is a link for you:

http://www.notebookcheck.net/SSD-versus-HDD-in-comparison.18750.0.html

Solution 2

Yes, but you are not comparing apples to apples. You are only looking at the BUS and the read/write speed; however, you are not accounting for latencies, which are always much lower in an SSD (basically any SSD on the market for SATA3).

HDD's didn't used to share the read/write often because the bigger issue then was how fast the platters could spin (4800, 5400, 7200, 10000) which was a direct relationship to the latencies and seek times (more-or-less).

Anyway, the Velociraptor typically maxes around 115 in the last tests I saw.

I'd suggest reading the article on Wikipedia about the performace characteristics of hard drives.

Comments

[ganesh]

750 MB/sec seems awfully high for SATA III. Physical signally is only 6 Gbit/sec. And 6000/8=750. But that assumes no overhead and perfect conditions. In praxis you need to divide between and and 11, which results in a max transfer rate of 550-600 MB/sec. -- As a confirmed expemple, take Intels ICH chipset with SATA-II (3.0Gbit/sec) which won almost every benchmark with speeds up to 270 MB/sec. SATA-III's bus speed is to twice that.

[Richard]

I figured but why doesn't the HDD list it's read/write speed like the SSD does? Do you have any benchmarks or anything I could look at, I've been trying to find some conclusive proof to persuade me.

[magicandre1981]

Because a HDD is limited by it platters and spindle. Moving the head to the right position takes some time. SSDs don't have this. SSD can be read much faster because it doesn't have an mechanic parts. The data are read from Flash modules. Here is a link for you: notebookcheck.net/SSD-versus-HDD-in-comparison.18750.0.html

[Richard]

ah i didn't think about the latency caused by the moving parts in HDD, that makes much more sense. And that's the benchmark I was look for, thank you