USB 3.0 HDD transfers at 300 KB/s...

[fuzzybabybunny]

So... I'm trying to figure this out.

I have an Asus UX32VD with three USB 3.0 ports. When I connect my Samsung S5 I have an app that tells me the charging current.

Two 3.0 ports charge at 450 mA and a third port only charges at 350 mA. Does this sound right?

I have a USB 3.0 2.5" enclosure with rotary HDD. It won't run on the 350 mA port and on the 450 mA ports it only transfers at 300 KB/s, with moments of ~10 MB/s.

I'm wondering if my USB ports are screwed up (driver issue?) or if my enclosure just isn't energy efficient enough.

 

[VirtualLarry]

That's pretty weak. USB3.0 ports are supposed to be able to source 800mA of current at 5V.

Is that with everything connected at once? Or singly?

 

[fuzzybabybunny]

That's pretty weak. USB3.0 ports are supposed to be able to source 800mA of current at 5V.

Is that with everything connected at once? Or singly?

Singly.

So are all USB 3.0 ports supposed to supply 800mA by default?

Sent from my SM-G900T using Tapatalk

 

[VirtualLarry]

So are all USB 3.0 ports supposed to supply 800mA by default?

"Up to". Devices negotiate with the host for power delivery. Could be a driver problem, I suppose.

 

[fuzzybabybunny]

"Up to". Devices negotiate with the host for power delivery. Could be a driver problem, I suppose.

Ah, I see. This is what I don't quite get:

In BIOS the USB supplies power at 450 mA. In Linux it supplies the same amount. In Windows 10 it supplies the same amount. It never seems to supply 800 mA, at least not to the S5.

Considering that drivers are OS-dependent, it shouldn't be something wrong with the drivers, right?

Sent from my SM-G900T using Tapatalk

 

[Insert_Nickname]

Two questions:

1) Is this running from mains or battery?
2) Are the ports connected to the same host controller?

In BIOS the USB supplies power at 450 mA. In Linux it supplies the same amount. In Windows 10 it supplies the same amount. It never seems to supply 800 mA, at least not to the S5.

It could be simply that the device (S5) isn't able to negotiate a higher current. The USB2 limit is 500mA after all. For full charging support you need a special charging USB port.

 

[fuzzybabybunny]

Two questions:

1) Is this running from mains or battery?
2) Are the ports connected to the same host controller?



It could be simply that the device (S5) isn't able to negotiate a higher current. The USB2 limit is 500mA after all. For full charging support you need a special charging USB port.

1. Mains and battery are the same.

2. Not sure. But with only one device connected (the other ports empty) the rate is still 450 mA.

Hmmm... So just the fact that it's a USB 3.0 port doesn't mean that it can automatically send out 800 mA? In addition to being a USB 3.0 port, it also needs to be a 3.0 port specifically designed to output 800 mA?

Sent from my SM-G900T using Tapatalk

 

[mikeymikec]

I doubt it's caused by drivers, but you could eliminate that from the list of possibilities by booting from a live CD and trying the transfer while in that session.

Have you tried another cable? Have you tried the drive on another PC?

 

[Insert_Nickname]

Hmmm... So just the fact that it's a USB 3.0 port doesn't mean that it can automatically send out 800 mA? In addition to being a USB 3.0 port, it also needs to be a 3.0 port specifically designed to output 800 mA?

No. Any USB3 port should be able to output 900mA.

However USB charging is a slightly different spec:

https://en.wikipedia.org/wiki/USB#Power

It may well be that the phone is itself limiting charging current when it detects a data connection. Or its simply limiting charging current on all non-original chargers (or just all non-USB charging compliant chargers).

Have you tried another cable? Have you tried the drive on another PC?

I was going to suggest exactly that.

OP; I'm assuming you're using the original charging cable?

 

[mikeymikec]

OP; I'm assuming you're using the original charging cable?

Hmm, the fact that this relates to a phone had escaped me - my wife basically had this exact scenario. I bought her a 3-metre USB cable to charge her Android phone (standard micro USB connector) to the mains adapter and some months later she noticed she was getting horribly slow charging rates. Change the cable, problem solved.

I think it's a "not all cables are created equal" scenario. I have two such USB cables from the same manufacturer with the same problem, however the cable that came with my first HTC phone can charge at the highest rate possible.

We also checked the power transfer using the 'ampere' app on Android, the dodgy cables gave far lower power transfer speeds (eg. 90-200mA) than the decent cables.

 

[myocardia]

Here is another vote for replace the cable first, before going any farther. It's the likely culprit.

 

[fuzzybabybunny]

Just a follow-up...

- tried lots of different cables. Same result. 450 mA

- hooked up an unpowered four-port USB 3.0 hub to one of the computer ports, then plugged the phone into one of the four hub ports. It read 1000 mA...

- as for the external USB drive, the reason it's acting so messed up isn't because there's inadequate power going to it. The drive has some bad sectors, causing it to eventually hang when I tries to read data.