Windows 7 kept turning off numlock on startup on the computer I just built. I found that some of the values for registry keys InitialKeyboardIndicators needed to be changed to 2 (numlock on). I found the directions in the [Microsoft Community](http://answers.microsoft.com/en-us/windows/forum/windows_7-hardware/want-to-set-num-lock-to-be-on-and-active-at/7b48ae6f-fa9c-4bc2-8359-81e0c5e5d6a2).