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How well do external DVD burners work?

PostPosted: Sun Feb 20, 2005 12:00 pm
by aristottle
I was looking at USB external DVD burners.......16X Dual layer.....how well do they work compared to internal?

Will I notice much of a difference in speed compared to internal drive?

How much faster is Fire wire than USB 2.0

External drives seem to be quite popular....why?

Thanks for the info guys.

PostPosted: Sun Feb 20, 2005 1:28 pm
by PadG
I don't see any difference in speed between external and internal burners. Instead of buying an external drive, get yourself an external enclosure for 5-1/2" device (look at places like www.newegg.com) and then buy a regular internal burner. It's very simple to install the burner into these enclosure, and the beauty of it is that you will be paying a lot less money than if you had bought an external drive.

There's a couple of extra bonus to putting together your own external drive. First, is that if you happen to change your mind about the external drive later, you can pop the drive out of the enclosure and pop it into your system. Second, if you have another IDE device, like another internal hard drive, that you may want to have a temporary access to, you can take apart one of these enclosure and remove the burner, replacing it with the new device in a couple of minutes.

Why are external drives popular? Portability. That's the key. One drive can be shared with many computers.

From what I had read, Firewire is supposed to have a better throughput than USB 2, IF you are transfering large files. In real life, I have 2 external (200 gigs) hard drive hooked up to my laptop via Firewire, and an NEC 3500 via USB 2 in an external enclosure, I don't see much difference in speed. I do have occasional problems with conflicts between the Firewire and USB 2 drives though, but that's probably attrributable to the drivers. Point is that I would recommend using either all Firewire, or all USB 2 for drives.

PostPosted: Sun Feb 20, 2005 4:17 pm
by rdgrimes
You will see a big difference in performance (speed) between HD's and optical drives in external enclosures. This appears to be mostly due to the lack of proper burner support in the external chipsets and MB controllers.

USB2 will never burn at 16x, at least nobody has yet demonstrated this ability. 8x is far more common, and 12x is rare but not impossible. Firewire is almost universally faster, 12 is common and 16x is possible but rare.

The primary issue with these interfaces seems to be throughput. That is, they don't really sustain a transfer at a steady rate that is fast enough for these burner datarates, and with a 2 MB buffer on the drive, that means frequent under-runs.

Firewire is certainly the best choice, because it delivers a much better throughput. I would look for the "Prolific" chipset in an external box if you wil be using a burner. For HD's, the chipset doesn't seem to make a lot of difference. In nearly all cases, read speeds are many times faster than write speeds, which may well tie into the burner issues.

If you are satisfied with 8x burning, and don't try a faster speed, it might not make any difference which you choose. But I also highly recommend going with a IDE drive in a generic external box. It's often cheaper, and far more flexable.

PostPosted: Mon Feb 21, 2005 2:24 am
by Jaybo
Well that doesn't make any sense, since USB2 is faster than firewire, tech-wise. Hmm..

PostPosted: Mon Feb 21, 2005 3:07 am
by dodecahedron
in theory yes, in practice no.
FireWire is better, belive all the users who tried both and compared.

PostPosted: Mon Feb 21, 2005 9:51 am
by Gen-An
rdgrimes wrote:You will see a big difference in performance (speed) between HD's and optical drives in external enclosures. This appears to be mostly due to the lack of proper burner support in the external chipsets and MB controllers.

USB2 will never burn at 16x, at least nobody has yet demonstrated this ability. 8x is far more common, and 12x is rare but not impossible. Firewire is almost universally faster, 12 is common and 16x is possible but rare.


This guy couldn't get 16x with his 716UF connected via IEE1394, but USB2.0 worked just fine: http://homepage2.nifty.com/yss/px716uf/px716uf2.htm

PostPosted: Tue Feb 22, 2005 5:08 am
by Jaybo
This is an interesting topic. I wonder if a tech site can professionally test this. I'd love to know why the results vary.

PostPosted: Tue Feb 22, 2005 9:49 am
by rdgrimes
I can tell you that my own hard drive benchmarks are about 30% faster on firewire than on USB2 for read speeds. (30MB/sec vs 20) Write speeds are much the same. Results for DVD burn speeds are similar, usually about 30% faster on Firewire, on both Oxford and Prolific chipsets.

There's an enourmous amount of variation between the different external chipsets, and they way they work with all the different MB controllers. There may be a certain amount of luck involved in getting a combination that works well. But unless you have a dysfunctional Firewire controller, it will always be faster than USB on sustained transfers.

PostPosted: Tue Feb 22, 2005 11:26 am
by LoneWolf
rdgrimes wrote:I can tell you that my own hard drive benchmarks are about 30% faster on firewire than on USB2 for read speeds. (30MB/sec vs 20) Write speeds are much the same. Results for DVD burn speeds are similar, usually about 30% faster on Firewire, on both Oxford and Prolific chipsets.

There's an enourmous amount of variation between the different external chipsets, and they way they work with all the different MB controllers. There may be a certain amount of luck involved in getting a combination that works well. But unless you have a dysfunctional Firewire controller, it will always be faster than USB on sustained transfers.


It will always have lower CPU usage as well. Big plus for many of us.

PostPosted: Wed Feb 23, 2005 8:54 pm
by tlotz
LoneWolf wrote:
rdgrimes wrote:I can tell you that my own hard drive benchmarks are about 30% faster on firewire than on USB2 for read speeds. (30MB/sec vs 20) Write speeds are much the same. Results for DVD burn speeds are similar, usually about 30% faster on Firewire, on both Oxford and Prolific chipsets.

There's an enourmous amount of variation between the different external chipsets, and they way they work with all the different MB controllers. There may be a certain amount of luck involved in getting a combination that works well. But unless you have a dysfunctional Firewire controller, it will always be faster than USB on sustained transfers.


It will always have lower CPU usage as well. Big plus for many of us.


I'll throw my 2 cents in here. I have found out myself before reading this thread how much faster firewire is than USB 2.0 for external hard drives. My WD external 250 GB USB 2/Firewire combo drive flies with firewire--40 MB/s sustained with 0--1% CPU usage! With USB 2.0, the sustained transfer is only 25.8 MB/s with 12% CPU usage. Amazing how much faster firewire is, and how little CPU resources it takes. I hear that firewire uses technology similar to SCSI to achieve the low CPU usage. So it seems that Firewire is the "SCSI" of external high speed interfaces, and USB 2.0 is the "IDE" of external high speed interfaces.

PostPosted: Wed Feb 23, 2005 9:29 pm
by VEFF
Talk about false advertising!
How can manufacturers sell 16X external burners that aren't even capable of more than 8X - 12X in the majority of cases.

I have never had an external DVD burner.
I always assumed they could burn at 16X since USB2.0 and firewire can burn at up to 50 and 60 MBPS or 400 - 480 MbPS, both of which are many times faster than data transfer rates required for 16X DVD writing.
I realize 400 and 480 are the maximum speeds attainable, but I always thought this was more than enough, until seeing rdgrimes' explanation.

(typed fast because I am in a hurry; will edit factual or typographical mistakes later if necessary).