Problems with jumping cursor
Information about the jumping mouse cursor problem, which occurs on some X41 tablets when CPU load is high.
When CPU load reaches 100%, the mouse cursor stutters and jumps to the bottom / middle of the screen (in Windows, just above the task bar). Additionally, left clicks may be generated.
Diagnosing the problem
In windows, it is possible to reproduce the problem by opening the calculator and typing 999999!
If the machine is affected, it will quickly become unresponsive (cursor stutter) and the cursor will eventually jump above the taskbar.
- ThinkPad X41 Tablet
Affected Operating Systems
- Windows XP
- Linux systems are ubiquitously afflicted since the issue is endemic with some 1.5GHz CPU's. Albeit, LINUX systems seemingly experience the occurrence less frequently because of superior resource management when performing comparable tasks inside Win32. The jumping cursor was confirmed with BackTrack 5r2 as of 08/19/2012 because BT includes native pen input features without patching. The jumping cursor occurred equally as frequently whether it is the LIVE booter or persistent install.
A workaround is being tested.
Undervolting the CPU seem to solve the issue (see TabletPCBuzz link below).
In Windows XP (and Vista?), this can be done using the Notebook Hardware control utility and the following voltages:
- 1500MHz model: 0.748V @ 6X, 0.796V @ 8X, 0.844V @ 10X, 0.908V @ 12X, 0.940V @ 15X
- 1600MHz model: 0.748V @ 6X, 0.796V @ 8X, 0.844V @ 10X, 0.908V @ 12X, 0.940V @ 16X
(values reproduced from the Any Updates Jumping Cursor? TabletPCBuzz thread)