Originally posted by: Roguestar
Originally posted by: Revolution09
1 Common sense would tell me that an internal SATAII drive would be much faster than an external USB, correct?
2 I'm reading on the Western Digital site that their internal drives have "Up to 3 Gb/s SATA transfer rates"
3 however on a local retailer's site they have listed "Fast -- Offers a 300 MB/s transfer rate - Three times faster than EIDE and twice as fast as SATA 1."
4 Surely they meant 3000 MB/s?
5 Because I'm reading that a cheap Seagate USB External has a transfer rate of 480 MB/s
1: Yes.
2: This is true, that's the maximum allowed by SATAII.
3: They mean 3000.
4: 3000MB/s = 3GB/s, but it is limited by the USB interface; it is the bottleneck.
5: Maximum transfer speed of USB 2.0.
Wow, Ms. Information there ..
1. Yes internal drives are faster then external.
2. Yup, but interface speed is not your concern. UDMA-5 (100MB/s) is enough (a side note, while formatting hdds of equal size but 2 IDE and 1 SATA, the SATA does finish about 20% faster, maybe due to the 2 IDE hdds sharing their bandwidth.. maybe someone can accuratly explain this).
3. 3Gb/s does not equal 3000MB/s (3GB/s, b & B difference). 8 bits per byte. 3000/8=375MB but take into account the 8b10b coding overhead of 20%, brings it down to 300MB/s, but then also take into acct that its 1024bytes per MB (not 1000) and you actually get (366*.8=) 292.8MB/s, right?
4. USB 2.0 max theoretical throughoutput of 480Mb/s (60MB/s), but any one device can only use up either 66% or 75% of said bandwidth, so a hdd can only use about 45MB/s, 55MB/s max. For most hard drives, thats about their max transfer rate anyways. Unless your transfering a lot of huge files, im sure you wont notice.
So "Surely they meant 3000 MB/s?".
NO, they said what they ment, and they ment what they said.
5. ECF (Error carried forward). No, they say 480Mb/s, see #4.
People buy external drives because they want/need portability. They dont dare open up their computer. They don't want the "hassle" of installing a new hdd. So you can turn off a hdd that you dont use all the time (ie storing pics/movies on, but only want to look at them 1/week lets say).
Ms. Information, from South Park, read as misinformation. You gave out a lot of incorrect info there
Roguestar.
Yup eSATA is exactly the same as SATA (from what little I've heard and using what common sense I have). I/we also havent gone into how firewire 400 or 800 have better throughput then USB 2.0.
Facebook
Twitter