Directly relevant paper http://www.seagate.com/docs/pdf/whitepaper/TP-535.pdf " The USB 1.1 and 2.0 specification requires that each USB port delivers at least 500 mA of steady-state current; however the majority of systems provide 700 mA of steady-state current. Most 2.5-inch disc drives meet this requirement only after they are already spinning and usually require a higher current during the initial spin-up profile. The majority of USB ports also allows for a higher current draw of 1000 to 1100 mA for a limited duration (instantaneous current) that allows the disc drive to spin up adequately. This capability varies from PC to PC and depends on a variety of factors such as the type of USB port, the USB controller used, the type of regulator and the type of capacitors at the host. " Marc Nicholas wrote: > Recently did the same myself -- resuced the 30Gbyte drive from my beaten up > Powerbook. Found a cheap aluminum USB case in my local Chinatown for > ~CDN$16. > > BTW...isn't USB rated for 5watts? i.e. 1A PER port, not 500mA? > > -marc > > On 10/27/05, Marcel Duchamp wrote: > >>I recently acquired a 30 gig 2.5" hard drive - out of a laptop in a >>dumpster. Occasionally needing to transfer more than will fit on a CD >>from work to home to work, I looked around for ways to use the drive and >>found this gadget: >> >>NexStar external 2.5" hard drive enclosure from www.vantecusa.comwhich >>runs from USB and also is USB powered. Mine came from Jameco but Vantec >>sells through other outlets as well. >> >> >>http://jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=453376 >> >>The cool deal: at Jameco, $17.45 each. It seemed to me to be a good >>bargain. They had others up to $70-80 or so. >> >>Performance: >>Win98SE - USB 1.1, about 1MB/s; >>WinXP - USB 2.0, about 10 times as fast, roughly. >> >>It came with a carrying pouch, a CD with Windows-only drivers, and a >>double headed USB cable. The cable allows drives that require more than >>500mA to get up to 1000mA. If you have a drive the needs more than >>that, there is a DC input jack but no power supply comes with the >>device. Mine did not work until I figured out which of the 2 usb plugs >>to use - the second one has power only and no serial wires. >> >>If you happen to have a 2.5" hard drive laying around, this might be >>useful to you. >>-- >>http://www.piclist.com PIC/SX FAQ & list archive >>View/change your membership options at >>http://mailman.mit.edu/mailman/listinfo/piclist >> -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist