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Is the USB port able to power a USB monitor?

Enrico D.

Member
Hello,

before to buy the Sp3 and Sp2, I already studied in internet the problem had people to connect a USB monitor like this one for example ASUS MB MB168B (15.6 inch full hd), it require around 5w power.

The problem is that the Sp3 usb port and even Sp2, is not able to give the power needed to start the monitor so people is using a Y cable to connect to the usb of the power supply of the Sp, and it work then, but you have additional cables and extension to organize. But this monitor is really nice and light/portable.

Do you have the same issue I think, correct?

Have you found some other full hd monitor powered via usb able to get directly the power from the USB 3 port in the device? Or it's impossible to bypass this issue and we need to wait future upgrade of Surface Pro?
I don't want to use the docking just for this because I can't travel with the docking... and it doesn't work well via mini displayport so I sold it and I have any intention to use it for now.

thanks for your help
 

malberttoo

Well-Known Member
Hello,

before to buy the Sp3 and Sp2, I already studied in internet the problem had people to connect a USB monitor like this one for example ASUS MB MB168B (15.6 inch full hd), it require around 5w power.

The problem is that the Sp3 usb port and even Sp2, is not able to give the power needed to start the monitor so people is using a Y cable to connect to the usb of the power supply of the Sp, and it work then, but you have additional cables and extension to organize. But this monitor is really nice and light/portable.

Do you have the same issue I think, correct?

Have you found some other full hd monitor powered via usb able to get directly the power from the USB 3 port in the device? Or it's impossible to bypass this issue and we need to wait future upgrade of Surface Pro?
I don't want to use the docking just for this because I can't travel with the docking... and it doesn't work well via mini displayport so I sold it and I have any intention to use it for now.

thanks for your help

I believe that the SP3 USB port supplies 3 watts. The power brick USB port supplies 7 watts.

So, find an HD monitor that requires a little less than 3 watts and you'll have it made.:D
 
OP
Enrico D.

Enrico D.

Member
thank you I never found those details, so I will remember 3 and 7, I wait to see if somebody so found a monitor of 3 w, but I doubt it can give so much quality to the screen, we will see. thanks for now, I wait other answers if will come.
 

Tsurugaya

Active Member
Top use the power brick for current to an external USB monitor would require a longer power cable, but it is a fairly standard cable, no?
 

surfdock

Active Member
Compliant USB 3.0 ports supply up to 900mA at a nominal 5v (4.5watts). However, the USB 3.0 spec allows for the voltage to be anywhere between 4.45v and 5.25v so as low as 4watts.

The SP3 power supply USB charging port supplies 5v@1amp so 5watts

The Asus spec sheet only says that the monitor typically uses less than 5watts and works via a single USB 3.0 cable: http://www.asus.com/Monitors_Projectors/MB168BPlus/specifications/
So Asus wants you to just use it without any extra cables. Maybe it will just work without any fuss?


USB "Y" power cables violate the USB spec and are not recommended by Microsoft, Asus, USB org, etc: http://compliance.usb.org/index.asp?UpdateFile=Policies#72
The Asus is not designed for using a different power supply, otherwise they would provide it in the box. So using one of these cables might void the warranty or something. Here is a link to the cable other folks are suggesting: http://www.amazon.com/USB-3-0-Male-Cable-Female/dp/B007VUF1HY

Overall, I think these USB-powered monitors are a great idea, but with the currently implemented standards, its a crapshoot as to whether you get seamless operation. Wait till USB 3.1 with universal bi-directional charging.


To workaround this whole issue, you could use a USB 3.0 powered hub like this:
http://www.amazon.com/Anker-Charging-Included-VL812-B2-Firmware/dp/B00EYXZI4M
 
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Tsurugaya

Active Member
I was curious because I have an AOC 15" 1366x768 monitor that I have no problem connecting to my SP2 and use it in either portrait or landscape.

However, when I connect it to my SP3 I get a long series of annoying USB connection beeps, the Display Link Core software downloads (while the beeping continues) and it never ever turns on. I've tried installing the driver separately, but I still get the continued USB connections beeps when I connect the monitor and it remains dark.

Since it works fine connected to the SP2 I know the problem can't be with the monitor, but it has to be with the SP3 and either the port or perhaps a problem of co=existing with the high resolution SP3 monitor. I just can't figure out where the problem is located.
 
OP
Enrico D.

Enrico D.

Member
Yes I connected already with the Y cable, but there is a problem! those cables are not pratical, you need other cable to make better extention... now I'm looking in amazon for cables to make the extention, and it is not so nice.

About the BEEPS I also had those, this happen because probabily the system is not able to give power to the monitor, or recognize something is wrong and not able to turn on the monitor.

With Y cable is all fine but one side that goes to the power supply usb or wall usb adaptor it's short, so we need at least a 1.5/2 meters extention female-to-male to arrive.. so you will see on the table 3 cables........

In fact now I was looking on amazon for a micro usb Y cable to eliminate at least 1 cable...... so a short micro usb segment will go to the Sp3, than a short USB 3.0 will be connected with a 2 meters extention and will go to seek the power... I 'm looking for something like this, to reduce to max 30 cm (3 feet) the cable asus-to-sp3... otherwise now you have:

1. 1 meter cable of asus to plug to the Y cable... from the Y cable you connect one USB to the sp3 device and another USB to an extention female adaptor that will be long around 2 meters to go to the wall power or to the power supply usb (at this point better to do not stress the usb of the power supply and attach to the wall).

Don't know, I was hoping could be more easy for a portable solution, but I will find a way.

Just wanted to know if some of you found some other FULL HD monitor able to plug directly.

I could reconsider the docking to connect... but it's not then a solution for to travel.
 

Tsurugaya

Active Member
@Enrico D.
I don't have the Asus, I have an AOC monitor. I did connect the y-cable to the USB port in the power brick. That turned the monitor on for a short while.
 
OP
Enrico D.

Enrico D.

Member
the sp3 usb support max 3 w. the usb of the power supply max 7

about the docking? the one able to give more w are the USB 3.0 ports correct? or however how many are giving watts and which is the maximum wattage there?
 

mtalinm

Active Member
I have been in touch with ASUS tech support regarding the MB168B+ (the 1920x1080 version; MB168B is the lower-res monitor). I had the same on-again-off-again issue whereas it works great with my laptop. I also tried manually splitting the cable with a Y extension but that did not work.

They sent me the following picture of how the monitor is to work with a Surface. I purchased a USB3 Y cable, on its way here in a couple of days, and will report back as to how well it works.

My lower-res monitor (Lenovo) works fine though.
 

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