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Windows 7: USB3 2.5" not working on USB2

13 Oct 2012   #1

windows 7 64bit
USB3 2.5" not working on USB2

Hi, i recently bought a USB3 2.5" 1TB toshiba drive and it works fine on my USB3 ports but it doesn't work on my USB2 ports. Non of the people i have asked seem to know why. i Have 3.5" usb3 2TB that works on both USB3 and USB2, so the only thing i can think of is that the 2.5" draws more power from the USB3 ports thus allowing it to run.

Any help is greatly appreciated, Thanks a lot.

Please if you read this and have any input at all post a reply. 87 views n no reply's, i cant be the first person experiencing this problem

My System SpecsSystem Spec
13 Oct 2012   #2

Win 7 Pro 64-bit 7601

First thing, try not using a USB3 cable to connect to USB2 ports (use a USB2 cable). Did the trick quite a few times.

In case that HDD is really hungry (which is possible as it was designed with USB3 in mind), look for Y USB cables (you can likely grab one for really cheap or DIY your own if you have some cables and the right equipment).

The main reason for its existence is drawing power from 2 USB2 ports to power one USB2 device. 2 USB2 toghether have the same power output as one USB3 (actually a bit more than one USB3), so it should run. Even if there are two ports "used", the transfer speed is still USB2, the second USB2 plug is there for power reasons only (and won't even get recognized as anything in My Computer)
My System SpecsSystem Spec
13 Oct 2012   #3
Mark Phelps

Win7 Pro 32-bit, Win8 Pro 32-bit

Does the 3.5" USB3 drive also have a separate power cord? IF so, that's why it works on the USB2 ports -- it's getting power separately.
My System SpecsSystem Spec


 USB3 2.5" not working on USB2

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