When typing, my cursor disappears. I then have to left click the page I'm on to get it back. I can type for about 20 seconds/100 characters, then I get a Windows beep warning. Any characters I'm typing stop showing up on the monitor. Same thing when I'm scrolling up or down a page: the cursor goes offline, and I have to re-click the page. I've tried various diagnostic/anti-virus software programs, but to no avail. I've repeated searched online, but no luck. My mouse settings are all in order, according to Windows 7 Control settings. I'm using Win 7 64 bit with 3.3Gb of Hz and ram. I had the same disappearing cursor problem one year ago, but it eventually went away. Why?