How many CD/DVD writers can I have attached via USB?

[jammer200022]

For CD/DVD duplication, how many external drives can I have attached to my PC?
The intention is to have 10 of them connected, say, and have them all copying.

Would this run OK?

Or would it overload the operating system?

I don't seem to be able to use the Nero support for mulitple recorders option.
Anyone know anything about that?

Any help would be appreciated.

Thanks.


Jam

[Dr. DOS]

USB can suppport as many as you want .... hundreds even via various hubs... however, should you try to copy more than two at a time I think you will get failures as you hd's will no doubt have trouble keeping up.... even at 1x copying. IMO

[jammer200022]

well, i've tried 2 at a time and it works fine!
i was just worried about the overload and thought i'd ask before going out and buying 10 external drives.

[SquirrelDip]

USB can support up to 127 devices but they all share the bandwidth. I believe that the bandwidth is per channel... Most modern computers have at least 4 ports so you should be able to run 10 - just don't plug them all into the same place...

[ViRaL1]

Most PCs have 4 ports but that's usually only 2 channels. In theory you SHOULD be able to get 480Mbps per channel, although actual throughput is much lower. If you have ATA-100/133 drives they should be able to keep up.

Here's one way to look at it.

1xDVD=1,385KBps

8xDVD=11,080KBps

10 X 8xDVD=110,800KBps

USB2.0=480Mbps or 61,440KBps (Per Channel)

Your total required HD output is about 108MBps.

You MIGHT be able to do it with SATA RAID (using Raptors) although I'd recommend SCSI.

If you can afford to reduce your burn speed (I'd recommend it just because a lock up will cost you 10 8x coasters), then your HD bandwidth requirement is cut in half and you're back in normal ATA territory.

Just remember these numbers are theoretical.
YMMV.