While using Windows NT 3.51 [ONLY IF upgraded with SP5], NT 4.0 [ONLY IF upgraded with SP6a], 2000 or XP, you may have encountered random "Keyboard (and/or mouse) ring buffer overflow" error messages in the System Log event viewer, spurious key clicks, or even sudden machine lockups, due to the (too) small keyboard and/or mouse queue buffer, because each hold only a maximum of 100 characters or clicks respectively (system default).
But all this can be fixed by tweaking the Registry...
To increase the keyboard buffer size, run Regedit and go to:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic
es\Kbdclass\Parameters
Look for (or create if not present) the "KeyboardDataQueueSize" DWORD [REG_DWORD] Value in the right hand pane -> double-click on it -> check the Decimal box -> double the value shown there (default is 100) -> type in the new integer number -> click OK.
Then, under the same Registry key, find/create the "PollStatusIterations" DWORD Value, and increase it from 1 (default) to 2 or 4, by performing same steps above, until your keyboard no longer exhibits interruptions.
To make your rodent "behave" by increasing its buffer size (with the Registry editor open), go to one of the following keys, depending on your installed mouse type(s):
ALL Mice:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic
es\Mouclass\Parameters
Serial Mice:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic
es\Sermouse\Parameters
PS/2 Mice:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic
es\i8042prt\Parameters
Bus Mice:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic
es\Busmouse\Parameters
InPort Mice:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic
es\Inport\Parameters
Microsoft Mice with IntelliPoint software:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic
es\msi8042\Parameters
USB Mice:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic
es\mouhid\Parameters
In the right hand pane, find (or create if not present) the "MouseDataQueueSize" DWORD Value -> double-click on it -> check the Decimal box -> double the value shown there (default is 100) -> type in the new integer number -> click OK.
Also, if you notice that your mouse clicks randomly WITHOUT you touching it, find/create the "MouseSynchIn100ns" DWORD Value -> double-click on it -> check the Decimal box -> increase the value shown (default is 20000000 = 2 seconds) to let's say 30000000 (3 seconds), or even higher if necessary -> type in the new integer number -> click OK.
To enable all buttons if using a 3 button mouse, edit (or create if not present) the "NumberOfButtons" String [REG_SZ] Value to read 3, under the appropriate Registry key(s) above, depending on your installed mouse type(s): Serial, PS/2, Bus, InPort, MS IntelliPoint or USB.
Close the Registry editor and reboot when done.