USB 3.0 Controller

[lancekidd]

I recently received a Dell Vostro 3550 laptop as a gift. I'm also taking the A+ in a week or two and want to ask a question that I've always been curious about.

The laptop has two USB 3.0 ports. Renesas Electronics is the driver and was set to start up in MSCONFIG. When I go to All Programs and open up the Renesas USB 3.0 Host Controller Utility, there is just a little box that pops up with an optional checkbox that says "disable USB 3.0 power management functions."

My questions are:
First of all, if I disable this utility from starting up with Windows, how does that affect the USB 3.0 from working? It still remains the driver for the port doesn't it? Also, if I check the box to disable the power management functions, what does that do?

I see a lot of drivers, graphics drivers for instance, that I always disable from starting up with the PC, but the drivers still work.

What purpose does it serve to disable this particular driver from starting up with the PC, or what purpose does it serve to disable the functions that it provides when it is still the driver that controls the Super Speed USB ports on the PC?

I hope this make a little sense, lol.

 

[goombawaho]

I think you are confusing DRIVER with any APP/UTILITY that runs in the taskbar or behind the scenes.

Nothing is going to work without the driver (sound, video, usb) if you disable it.

The other items are things such as Sound Card Control Panel, Nvidia control panel, etc. These are fine to disable.

Disabling power management is fine for items like USB and network cards so they don't disconnect you.

 

[rclarke250]

The power management for the port is for charging devices connected to the port, i.e. cell phones,mp3 players,and cameras to name a few. from the wiki page: In Battery Charging Specification,[38] new powering modes are added to the USB specification. A host or hub Charging Downstream Port can supply a maximum of 1.5 A when communicating at low-bandwidth or full-bandwidth, a maximum of 900 mA when communicating at high-bandwidth, and as much current as the connector will safely handle when no communication is taking place; USB 2.0 standard-A connectors are rated at 1.5 A by default. A Dedicated Charging Port can supply a maximum of 1.8 A of current at 5.25 V. A portable device can draw up to 1.8 A from a Dedicated Charging Port. The Dedicated Charging Port shorts the D+ and D- pins with a resistance of at most 200 ?. The short disables data transfer, but allows devices to detect the Dedicated Charging Port and allows very simple, high current chargers to be manufactured. The increased current (faster, 9 W charging) happens if both the host/hub and devices implement the new charging specification.

Also: Sleep-and-charge USB ports can be used to charge electronic devices even when the computer is switched off. Normally when a computer is powered off the USB ports are powered down. This prevents phones and other devices from being able to charge unless the computer is powered on. Sleep-and-charge USB ports remain powered even when the computer is off. On laptops, charging devices from the USB port when it is not being powered from AC will drain the laptop battery faster. Desktop machines need to remain plugged into AC power for Sleep-and-charge to work.