Windows 7: USB ports stop working w/ too many devices

My setup:



Acer Aspire with Windows 7 Ultimate w/ the latest Windows updates
4gb of Ram
Intel Core 2 Duo Processor

Don't think that much more is relevant.

I use a usb wireless device on my computer and if only it and my keyboard are plugged into the usb ports it seems to work fine.

I have 2 monitors, 1 has usb ports on it, so I have a cable running from it to a usb port as well. Even with this, everything works fine.

When I try plugging in something as simple as my Logitech wireless mouse's receiver, eventually my usb ports will stop working and I must manually cut the computer off by pushing the power button. Otherwise, the computer will get stuck at "Shutting Down..." and remain so until I manually cut it off.

In some instances, I have only plugged in a Seagate 500gb external hard drive and a SanDisk 4gb flash drive. When I do this, the usb ports stop working before I can do anything, again, a manual restart is requried.

So far I've tried removing things one at a time, but the result is the same once the usb ports get "overloaded."

I read about installing the latest drivers from the manufacturer, but all I get as a description of the usb ports is the generic description of them.

Hi MB and welcome

Could be as simple as your PSU. USB uses +5volts and if your psu is marginal the 5volt circuit may drop to less than that.

Tell us about your system

Ken J

Zig is on the right path. It sounds like you dont have enough power for all the items.
The best thing to do is get a Powered USB Hub, they around about $40 for a powered one the cheaper ones will only cost 20 but are non-powered with trying to use a mouse and hard drive both are heavy power items I would recommend getting a powered hub.

I actually replaced the power supply to a 650 so that my nVidia 9800 gtx + would have enough power running to it. I had the same things hooked up occassionally in windows vista.

MB

You know in terms of the USB, its not the total wattage that is important but how much amperage it can put into the 5 volt rail. Might want to check the specs. Unpowered usb devices can cause all sorts of random craziness

Ken J+

I have I think the same issue. All I have plugged in is basic USB Mouse and keyboard (they work fine) but when i plug in a universal laser (runs as a printer basically), after about an hour of idling all the rear usb ports shut down (except keyboard and mouse), and unplugging and replugging the device doesnt fix it. If I swap the plugs of the laser for where the mouse is, the same thing then happens to that usb port. All power saving features have been disabled (including selective suspend). Drivers uninstalled and reinstalled.. So far the problem doesn't seem to be occuring if I use the front USB ports, or if I plug a USB hub (not powered) into the back of the computer. In this situation it doesnt appear to be shutting down the ports after an hour or so. I Also get the same problem where once the usb ports crash, my computer will hang while shutting down. I will get an shutdown error on next restart saying I blue screened. This computer is brand new. These USB ports are meant to provide extra power or something. On the watt metre on the wall my computer never goes over 100 watts, so I assume it cant be a too weak power supply? I see similar problems to this everywhere, with no solution as of yet. Any suggestions would be great. If there is other info i need to provide let me know.

USB self-powered ports are limited in how much juice they can provide. DarkXeno put you on the right track with his recommendation of a powered hub.

Yeah the odd thing is I dont think I need one. As I mentioned I've used a non powered hub with no issues. And during use the Laser runs fine. It is only if I go afk for an hour or so and come back to work that the rear USB ports freeze up (excluding USB KB and Mouse). Today I opened device manager after I came back and double clicked on root hub, and when i clicked on power tab it stopped responding. Seems like a driver incompatability with windows and the gb mobo?

There is no hibernate and nothing switches off except the screen. I know the obvious solution is to use the hub, but I have like 6 unused ports on this mobo (only kb and mouse). I've seen this issue numerous times I think, and always the same uninstall drivers / reboot.. update bios.. use powered hub (for a self powered device like a laser?). This is the first time I've ever experienced this with a computer. And I have 2 other gigabyte mobo/windows 7 PCs.

Any direction as to what sort of issue it appears to be is great. I don't think it's the lacking in power one in this case.

Each USB port on your PC is limited to 500ma max current draw. If you exceed that the +5V rail for that port will shut down to prevent an overload. It's been my experience the ports usually shut down in pairs of two. You have to power down the PC to reset it. If you use an unpowered hub every device plugged into it will try to draw what power it needs from the one USB port the hub is plugged into. If you plug a couple of power hungry devices into the one hub there is a good chance the USB port will shut down. As posted above you can see how much current is being drawn if you know where to look. I personally don't use an unpowered hub unless I absolutely have too. Anything with it's own power pack probably doesn't draw any power from a USB port, just DATA. Just some info to file away some where for future use.

A Powered USB Hub is cheap. Get one and don't be surprised when your problems vanish.