Re: Samsung T5 500 GB USB3.1 SSD fails with ASMedia ASM1142, 250 GB version works

[Jonathan Woithe <jwoithe@just42.net>]

On Mon, Feb 22, 2021 at 09:47:07PM +1030, Jonathan Woithe wrote:
> On Mon, Feb 22, 2021 at 11:24:18AM +0100, Oliver Neukum wrote:
> > It is possible that the other machine can just supply more power.
> 
> On the machine with the ASMedia controller (where the problem occurs), the
> 500 GB SSD works perfectly well when connected to USB2 sockets.  If a USB2
> socket can supply sufficient power, wouldn't a USB3 port be more than
> capable?
> 
> The specifications for both the 250 GB (working) and 500 GB (not working)
> are 5V at 0.8A.  I'm guessing this is a worst-case scenario.  In any case,
> this is well within the capabilities of a USB3 port.  If there was a power
> issue with one of these drives it's surprising it's not seen in both -
> unless the 250 GB is just under the critical power threshold and the 500 GB
> is just above it.  Is there an easy way to tell if this is indeed the case?

Another datapoint: on the system with the ASMedia controller where the 250
GB T5 SSD works but the 500 GB T5 SSD does not, the same USB3 socket is able
to power a traditional 2.5" spinning rust hard drive without any obvious
problems.

Regards
  jonathan