Portable External Drive

All external 2.5"'s I've seen require 1 USB2 port. USB1 does not provide enough power and you need to use a "Y cable" to plug it in and get the power of 2 usb ports.
 
rorz0r said:
All external 2.5"'s I've seen require 1 USB2 port. USB1 does not provide enough power and you need to use a "Y cable" to plug it in and get the power of 2 usb ports.
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Yes but are those pre-assembled 2.5" HDDs, or are they separate 2.5" enclosures?

I had a Transcend StoreJet in the other day. 640GB. I was shocked to find that it required 2 x USB. And it wouldn't even get enough power connected to my front USB ports - had to plug it in at the back! Shocking. PoS.
 
PostmanPot said:
Yes but are those pre-assembled 2.5" HDDs, or are they separate 2.5" enclosures?

I had a Transcend StoreJet in the other day. 640GB. I was shocked to find that it required 2 x USB. And it wouldn't even get enough power connected to my front USB ports - had to plug it in at the back! Shocking. PoS.
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Both. PoS indeed... 500mA should be enough for any 2.5" and according to the usb2 standard any (and every) port should be able to supply that.
 
The older 2.5" Seagate FreeAgent drives were also supplied with Y cables, not sure about the current generation.
 
Nope. I guess they assume everyone on usb2. Bit of a fail if you buy one and only have usb1 and it doesn't work.
 
ponder said:
Pooky, go get a 2.5" Internal from Matrix Warehouse, just give them a call first and ask Neil if they have stock.
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Ask for Neil indeed.....then call him an Englishman and say TopCa7/Fooly says hi :D

EDIT: Actually kinda funny, hes bringing me a 500gb external 2.5" right now :P
 
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PostmanPot said:
Yes but are those pre-assembled 2.5" HDDs, or are they separate 2.5" enclosures?

I had a Transcend StoreJet in the other day. 640GB. I was shocked to find that it required 2 x USB. And it wouldn't even get enough power connected to my front USB ports - had to plug it in at the back! Shocking. PoS.
Click to expand...

Weird, I have the exact same drive and it works fine without the Y cable, connected to the front USB ports and on the Mede8er
 
USB 2.0 provides up to 5.25 V and a maximum of 500 mA can be drawn from a port. The specs of the Transcend Storejet 640GB say 5 V required, so I can't see why it wouldn't work with power from just 1x USB 2.0 port.
 
South_Bit said:
USB 2.0 provides up to 5.25 V and a maximum of 500 mA can be drawn from a port. The specs of the Transcend Storejet 640GB say 5 V required, so I can't see why it wouldn't work with power from just 1x USB 2.0 port.
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And do front USB ports provide the same output as rear USB? Tried on two PCs, and it needed two ports. The unit comes with a Y cable.

Faulty unit?
 
PostmanPot said:
And do front USB ports provide the same output as rear USB? Tried on two PCs, and it needed two ports. The unit comes with a Y cable.

Faulty unit?
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The front USB ports may provide a slightly (insignificant?) lower output voltage when compared to the back ports due to the larger voltage drop occurring over the longer length of copper (internal case wiring from jumpers to the front of the case). The real problem is the available current per port (up to 500mA) which some PC's can't seem to deliver and it's just enough for some 2.5" hdd's. What drive is inside Transcend? Mine's a Samsung (you can check it without opening it in HDD Scan)
 
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D4N said:
The front USB ports may provide a slightly (insignificant?) lower output voltage when compared to the back ports due to the larger voltage drop occurring over the longer length of copper (internal case wiring from jumpers to the front of the case). The real problem is the available current per port (up to 500mA) which some PC's can't seem to deliver and it's just enough for some 2.5" hdd's. What drive is inside Transcend? Mine's a Samsung (you can check it without opening it in HDD Scan)
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I don't have it any more, so can't check.

Did your come with a Y cable?
 
It the drive is supplied with a Y cable then it required to be connected to 2 X USB ports for adequate power for the drive.

The max power output for USB 2.0 is, as Lounger said, 5V nominal @ 500 mA and again there should be no noticeable differences between front and rear ports at all, unless shortcuts are taken on motherboard, wiring harness, or case, or any combination of these.

The only possible exception should be the new Gigabyte motherboards that advertise "3X USB power" ports, for iPod/iPad charging. I don't know if other manufactures will follow suite by offering ports with "non-standard" power outputs for this purpose. Probably.
 
kayvee said:
It the drive is supplied with a Y cable then it required to be connected to 2 X USB ports for adequate power for the drive.
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Yup, it came with a Y cable. So I am now perplexed at how D4N's StoreJet gets power from 1 x USB port.
 
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