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Will an external USB DVD writer perform the same like Internal SATA DVD Writer?

I'm going to purchase a new PC with a very sleek cabinet. If I buy an external USB DVD writer will it perform the same like an internal SATA DVD Writer?

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It depends on the specifications of the external drive. I believe the fastest CD write speed is 52x, so if you find a drive (and discs) rated for that speed there shouldn't be a difference.

With a SATA drive you have a 1-3 Gbit/s transfer speed. USB 2.0 has a transfer speed of 480 Mbit/s.

I am just now noticing that this a DVD writer, and DVDs read at 1.32 Mbyte/s. Multiply that by 8 and you're at 10.6 Mbit/s. Note that this is under the limit of USB transfer speeds.

Further reading can be done on the Wikipedia Optical Disk Drive page.

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ok but what about USB and SATA transfer speed. Doesn't they matter – metal gear solid Mar 23 '10 at 4:18
Not for DVDs. DVD's read at 10.6Mbit/s and SATA I is 150Mbit/sec. You're good. – LawrenceC Dec 23 '13 at 18:11

I think Josh K is pointing out that the fastest optical drives don't get anywhere near saturating even the USB interface. Since SATA is much faster still, it's just even more underused by a DVD drive. DVD = slow, USB = way more than fast enough for DVD, SATA = ridiculous overkill for DVD.

The only relevant factor here is the quoted speed of the drive. If DVD read speed = 1.32 Mbyte/s x (quoted speed of the drive), then a 48x drive can only transfer a maximum of 1.32 Mbyte/s x 48 = 63.36 Mbyte/s of data. And that's in read mode - write mode is much slower. Josh points out that even the relatively slow USB interface offers 480 Mbit/s.

Any two same-model drives quoting (say) 48x read speeds and 20x write speeds should perform identically, however they're installed and connected, because the drive mechanism itself is the limiting factor. SATA and USB are built to cope with hard drives, the slowest of which is very much faster than the fastest DVD drive.

All you need to consider is what is the fastest drive that you can afford, and whether the greater convenience of an external drive is worth more to you than the extra cost of its case and the footprint on your desk.

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Are you sure the 48x is with respect to the base DVD speed (10,800 kbit/s)? Couldn't it be with respect to the original CD-ROM speed, 150 kbit/s? (Although that would put it below the DVD speed, x70.) – Peter Mortensen Dec 23 '13 at 18:21
The highest listing on Wikipedia is currently x24. – Peter Mortensen Dec 23 '13 at 18:51

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