The problem is probably the use of shared IRQ's for different hardware parts. Having shared IRQ's, especially with the video card, can cause all sorts of intermittently strange behavior on Windows as well as Linux, and Dell machines are just as susceptible as any other brand. Its like something cannot keep up with arbitrating hardware requests. I have taken the same Dell Optiplex machine, running a dual boot of XP and Fedora, and it displays the same problems on both OS's. First, try to disable any serial and parallel ports you don't need, as well as network adapters, or anything else using IRQ's; the goal is to free up those resources for other things. Try to run a utility (some BIOS will do this as well) to display IRQ's and find out which ones are shared: you will probably find the USB channel in question is being shared with something else, perhaps the video card or sound card. Anything shared with video cards seem to increase the risk of this problem, and GPIB and DAC cards from National Instruments are notorious for this problem. Reallocate the IRQ's by disabling ports, moving the cards around in the slots, etc. Also make sure you are running the latest BIOS, or experiment with BIOS versions. If you can get it so that the USB channel is on its own IRQ, the problem should go away. Or at least have it shared with a low-use IRQ, like a serial port. -----Original Message----- From: fedora-list-bounces@xxxxxxxxxx [mailto:fedora-list-bounces@xxxxxxxxxx] On Behalf Of Matt Florido Sent: Thursday, May 26, 2005 12:46 PM To: fedora-list@xxxxxxxxxx Subject: Re: Disappearing USB mouse On Thu, May 26, 2005 9:07 am, Botond Kardos said: > Hi, > I have a DELL Optiplex GX260 with FC3 and kernel 2.6.11-1.14. My > mouse (standard Dell USB->PS/2 mouse) sometimes stops responding and I > have to press Ctrl-Alt-F1 and Ctrl-Alt-F7 to make it work again. This > behavior is quite rare normally except during Unreal Tournament where it > is very frequent (about twice in a minute) and very irritating. I've > rebuilt the stock kernel with preemption but there was no difference. Of > course there's nothing in /var/log/messages or /var/log/Xorg.0.log. Does > somebody has an idea what can cause this? I have the same problem on occasion with a Dell SC420. Interestingly, it doesn't occur when I use the ports on the front of my server. Worth a shot if your Optiplex has the same. -- Regards, Matt Florido -- fedora-list mailing list fedora-list@xxxxxxxxxx To unsubscribe: http://www.redhat.com/mailman/listinfo/fedora-list The information contained in this e-mail including any attachments may constitute Corvis Equipment Corporation Proprietary Information that is subject to Non-Disclosure Agreement and cannot be disclosed to any other party without the express consent of Corvis Corporation. If you are neither the intended recipient of this e-mail nor responsible for delivering this e-mail to the intended recipient, note that any dissemination, distribution, copying, or retention of this e-mail is prohibited. If you believe you have received this e-mail in error, we request that you notify the sender by return e-mail and then delete this e-mail and any return email immediately.