External drive power

[VectraMan]

I've bought a "Dabs value" drive enclosure and put in a 120GB ATA drive from my old PC. Took 5 minutes to fit and all worked first time.

The description says "Powered by external AC power adapter or bus power", but I can only get it to work with the adapter plugged in.

Should these things be able to work just with power coming off the USB cable? Or do I need a different cable, or is it that the drive I have just needs too much power for USB? Anybody know how all this works?

[Durbs]

If its a full size ATA drive then, no, USB cannot provide enough juice for these. It'll only be able to power a smaller laptop stylee drive.

[VectraMan]

Ta. Makes sense - it was quite a fast drive in its day. In the enclosure it pulls 9W from the mains.

It never seems to spin down either, even when it's disconnected from a PC.

[Durbs]

Apparently Firewire can supply up to 30v compared to USB's 5v - is there a Firewire socket on it too or just USB?

My external HD has both but i haven't got a Firewire port on my PC to see if it works.

[Ken Dodd]

drives

I had a good 250gb hard drive from a laptop that was bolloxed. I bought a cradle (abt £10) from the local Computer shop and installed it in that. The reason I mention it is because it only uses USB power but it has TWO plugs on the lead and both need to connected to USB ports to work - it needs all the power apparently.

Plus I now have a 250gb external drive - which is handy.