Keyboard cursor blinks too quickly or slowly due to cursor blink-rate settings.
Cause:
The cursor blink-rate slider is set too high or too low on the cursor blink-rate slider bar.
Solution:
Double-click 'Keyboard' in 'Control Panel' and adjust the cursor blink-rate slider bar.
1) Click the 'Start' button to display the 'Start' menu.
2) Select 'Settings' and select 'Control Panel'. (The 'Control Panel' window appears.)
'Control Panel'
3) Double-click the 'Keyboard' icon. (The 'Keyboard Properties' dialog box appears.)
'Keyboard' icon
4) Click the 'Speed' tab.
5) Adjust the cursor blink rate in the 'Cursor blink rate' group:
a) Place the cursor on the slider.
b) Click and hold down the mouse button while moving the slider to either a slower or faster position; then release the mouse button.
NOTE: The selected rate is shown by the blinking cursor to the left of the slider bar.
Cursor blink rate
6) Click 'Apply' and click 'OK'.