I've been having a persistent problem with my mouse (and also keyboard, to a lesser) extent. I'm at my wit's end trying to figure out what is going on here.
The mouse in question is a Razer DeathAdder 3.5G (high-precision wired USB mouse), and the keyboard is some generic "Dynex" brand POS I got cheap years ago. The problem does not appear to be specifically related to either piece of hardware, though.
The gist of the problem is that, periodically, the mouse cursor becomes very erratic. It'll bounce left and right and up and down a few pixels as I move it around on the screen. Sometimes it'll go completely wonkers and move straight left when I push straight up, for instance. It makes for some interesting art in Paint/GIMP when I try to hand-draw straight lines, especially when it decides up=left or some nonsense and goes off in that direction while bouncing up and down a few pixels in the process. It does seem that it wants to bounce left and right far more often than up and down, and that it tends to favor up=left and down=right (to a degree, more perhaps a 60 degree angle).
Fixing the problem entails lifting the mouse up and putting it down. About half the time, after doing this, the mouse begins acting right. Conversely, if the mouse is already acting right, then lifting it up will cause it to start acting badly afterward. It'll also start acting up on its own, after a period of time that can range from a few minutes to an hour or two, though usually on the lower end.
The problem is always present after booting up into either of my OSes (Windows 7 Professional x64 and Fedora 14 x86-64). Unplugging and replugging the USB cords also causes the issue.
Very oddly, about perhaps 10% of the time, after swapping cords in and out or booting up, the mouse will act perfectly all day. However, the keyboard will then act funny, occasionally sending keys I'm not pressing at all, sometimes in long bursts of a single key, other times just a single "ghost" key press every now and again. It seems to favor 'd', 'k', and page up and page down, though not always. It does make editing files in Vim a bit of a pain when it starts spamming 'd' over and over again.
I have replaced my motherboard (an ASRock A780FullDisplayport, now a Gigabyte GA-MA785GM-US2H). This had no effect. It's definitely not the specific motherboard, though I warrant it may be a general issue with the chipset (780G to 785G, which I believe are more or less the same thing).
I have swapped mice with a friend who has an identical mouse. Either mouse works perfectly on his computer and never glitches or behaves erratically, ever. Both mice exhibit identically irritating behavior on this machine.
The old mouse (a cheap Logitech, don't know the model name) that I replaced with the DeathAdder exhibits the behavior, albeit far less so. I had actually originally thought the mouse was the problem and bought the new DeathAdder mouse to fix the issue. It turns out that a higher DPI just means the cursor jumps around further, so all that did was make things worse. I can turn down the DPI on the DeathAdder, which makes it more tolerable, but I can still see the cursor jumping back and forth by a few pixels (like the old mouse did).
I have tried a number of surfaces, including the desk surface, cardboard, white paper, my friend's mousepad, and even a Razer mousepad marketed as being designed for the DeathAdder. The problem persists on all of these surfaces. Razer seemed pretty hung up about the surface being the likely issue, despite me telling them I've tried multiple ones, despite trying it in multiple rooms (three different apartments in two different states, for that matter) with different lighting conditions and different electrical interference possibilities, and even despite me using one of their own damn mouse surfaces. I don't blame them much, though, since the issue does not appear to be their mouse and so really isn't their problem.
I tried using a different keyboard for a while in case they were conflicting. Same behavior.
I have worked with all other USB devices unplugged from the time of boot up, with no change in behavior. Having my iPhone plugged in or left in my car doesn't make a lick of difference, nor does having my APC UPS plugged in or my XBox360 gamepad. Heck, the behavior started back before I even had any USB devices besides the keyboard and mouse.
I am absolutely positive this is not a virus. Aside from the fact that it happens in two different OSes, it also happened during the Windows 7 installer, inside Linux LiveCDs, and so on.
Having bought an $80 mouse to fix a not-broken mouse, and then a $30 mouse pad to fix a not-broken desk surface, and just today having rebuilt around a new $80 motherboard to fix a not-broken motherboard, I'm naturally getting to the end of my patience. I can't for the life of me think of what else could cause this issue. I'd imagine that if the CPU (Phenom Agena 9550) or RAM (G.Skill DDR1066 2x2GB) were faulty, I'd be having a ton of stability issues, but I'm not; everything works flawlessly all day long, gaming or coding or web browsing, except the damn mouse (and keyboard, sometimes). It's not the motherboard, as I've replaced that now.
I thought heat and the chipset may have been an issue, but between a new motherboard and a bunch of new fans, I don't think that's an issue anymore. At least the computer is running a lot cooler now, even if it didn't need it.
Is it possible it's the PSU (OCZ ModXStream Pro OCZ700MXSP) ? Or the video card (Sapphire 100277L RadeonHD 4770) ? Could the case (Thermaltake LANBox Lite) somehow be grounding the USB port or something? Could the disk drive (WD Caviar Green 1TB SATA, WD10EADS) or DVD-RW (Samsung SATA, SH-S203N) magically cause this? Martian ray guns?
I've been back and forth with Razer support, hoping they'd have a clue, but they don't. They finally just told me to wipe Linux off the drive "in case there's an incompatibility," at which point I lost interest in their help... that idea doesn't even make sense. They wanted me to verify it wasn't a driver incompatibility, but the issue happened when I reinstalled Windows 7 today inside the installer environment itself.
The keyboard issue is a lot harder to get much of a feel for as it happens so rarely. I have to juggle cords around or reboot and then play around with the computer for a while to even see it happen once, much less start to trigger consistently. Granted, the keyboard is sending far fewer USB events/packets than a high-DPI mouse, so that's not entirely surprising.
Aside from replacing the entire damn machine, what else can I check or try to solve this issue, or at least identify the root cause of the issue? I just want to be able to use my computer in peace without having to lift up the mouse every 20 minutes to fix erratic behavior, and it'd be swell if I could even play a few games without gun-glitching all over the place in an action scene. :/