FireWire 'greenest interface' says FireWire Trade Association

Recent low-end Macbooks lack FireWire ports
Recent low-end Macbooks lack FireWire ports

A report from the 1394 Trade Association, the worldwide organisation for the promotion of FireWire, says FireWire is not only the fastest interface for connecting accessories but potentially the greenest, too.

Consultant Bill Rose crunches the numbers, starting with the fact that FireWire can provide up to 45W of power - eighteen times the meagre 2.5W available over USB.

This means devices such as external hard drives could be made to operate entirely from power supplied by a computer, instead of using AC adaptors, many of which waste large amounts of electricity from being permanently plugged in.

High speed = low power

He goes to note that FireWire's maximum throughput (800Mbps) being four times that of USB 2.0 means, again theoretically, that external hard drives with USB connections will take longer to complete the same task.

Rose estimates that USB drives use 40 per cent more power for typical applications and 300 per cent more for demanding tasks like backups and copying files.

Rose also believes 'anectdotal evidence' shows that USB devices use up to four times more CPU cycles to service the port, meaning more processor and cooling power wasted.

However, Rose does concede that despite FireWire's maximum power output of 45W, only a handful of network cards provide even 18W, while Apple computers are limited to just 7W of output - hardly enough to power many accessories.

And now that even Apple is backing away from the interface, the likelihood of any major manufacturer creating a FireWire-only device without either USB port or AC adaptor seems rather slim.

Still, for the few FireWire hold-outs, it's nice to know you're doing your bit for the planet.

Via Greentech Zone.

Mark Harris is Senior Research Director at Gartner.