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JHo1 · Jan 14, 2007, 11:32 AM

Hi
I wonder if anyone can offer any help on an odd problem I'm having with a Logitech wireless keyboard & mouse?

The receiver has a cable with 2 connectors, the instructions say (for a desktop) connect the mouse ps2 connector into the mouse ps2 port and the keyboard usb connector via the supplied usb to ps2 connector into the keyboard usb port. So far so good and it works.

My 4 rear USB ports are occupied by; scanner, printer, external disk. No problem, everything works. But when I add a 4th USB device, a card reader, the PC loses sight of the mouse 50% of the time. The keyboard is fine. I seem to have a 50% chance of the PC seeing the mouse after booting. When I say "seeing" I mean that if I go into control panel etc the mouse information is empty, the PC can't even see there's one there.

I've tried using one of the front USD ports - same result. I'm afraid I've tried so many combinations & permutations that I can only say I think I've tried unplugging other USB devices and it makes no difference but I'm not certain on that.

I've also tried using just the USB connector, into a USB port not via the converter, but that left me keyboardless :(

It's not the world's biggest problem, hot plugging the card reader works, but it's one of those annoying, "it should work so why doesn't it", problems.

Thanks,
John

StuMegu · Jan 14, 2007, 12:43 PM

Hi, are the other devices self powered or do they get their power from the motherboard, if the latter you might want to consider getting a powered 4 port usb hub and plugging some devices into that to spread the load!

JHo1 · Jan 15, 2007, 12:02 PM

Thanks Stu, the scanner and the card reader take power from USB, the remainder have a brick each. That did cross my mind but I thought it unlikely when I got the same problem using the front USB ports. You've just reminded me though that I do have a powered hub gathering dust somewhere, I'll try that.
Thanks,
JH

StuMegu · Jan 15, 2007, 02:21 PM

If you want to check the power consumption, go to "usb root hub" in device manager and look at the power tab, that should tell you what is draining what power from the system and will suggest which device to move to the powered hub!

Scouter · Jan 16, 2007, 08:31 PM

Originally Posted by JHo1

Hi
I wonder if anyone can offer any help on an odd problem I'm having with a Logitech wireless keyboard & mouse?

The receiver has a cable with 2 connectors, the instructions say (for a desktop) connect the mouse ps2 connector into the mouse ps2 port and the keyboard usb connector via the supplied usb to ps2 connector into the keyboard usb port. So far so good and it works.

My 4 rear USB ports are occupied by; scanner, printer, external disk. No problem, everything works. But when I add a 4th USB device, a card reader, the pc loses sight of the mouse 50% of the time. The keyboard is fine. I seem to have a 50% chance of the pc seeing the mouse after booting. When I say "seeing" I mean that if I go into control panel etc the mouse information is empty, the pc can't even see there's one there.

I've tried using one of the front USD ports - same result. I'm afraid I've tried so many combinations & permutations that I can only say I think I've tried unplugging other USB devices and it makes no difference but I'm not certain on that.

I've also tried using just the USB connector, into a USB port not via the converter, but that left me keyboardless :(

It's not the world's biggest problem, hot plugging the card reader works, but it's one of those annoying, "it should work so why doesn't it", problems.

Thanks,
John

I had a similar problem with my usb keyboard which has 2 usb ports as part of the keyboard. The computer itself had 2 usb ports near the keyboard ps/2 port, and two more pci cards one with 2 usb ports the other with 4. I came to the conclusion that there is a physical limit to the number of usb devices I could attach. I got around it by using a usb hub which had its own power source.
You can manage with less as long as you disconnect and reconnect to the same port. If you leave all connected either mouse or keyboard fails or both.
Logitech site also gave me some clues.

JHo1 · Jan 17, 2007, 12:15 PM

Stu, Scouter, that's fascinating, thanks. The scanner is drawing 500ma, hardly surprising, but only one other USB port shows that tab and that is drawing zero. The machine obviously recognises what is on the other end and has amended the description so rather than "USB hub" it says "USB mass storage". But it's not letting on what the total power drain is :-( Never mind. A hub seems the way to go if I ever need more ports. And fortunately I have one lying around. Thanks guys.
John