Odd mouse behaviour

[Seth]

The PS/2 should be the touchpad.

 

Try Safe Mode and this as well:

 

When the slowness occurs, press ctrl-alt-delete at the same time to open Task Manager. Click on the processes tab and post back with any processes that are consuming more than 10% of the cpu or more than 100,000K of ram.

[TheSlee]

just HL2.exe (the game) but the number under 'CPU' increases steadily through gameplay and then goes waaaay back down after the slowness and during the slowness, the CPU usage % goes from about 50% to 98-99% but the memory usage stays the same.