My keyboard intermittently stops working. Sometimes a couple of keys will work, but usually none. Sometimes if I mash the ctrl+alt+windows keys randomly for a bit, the keyboard will let me type one more letter before stopping again. Sometimes the keys will open a program menu but usually not.

I have even completely wiped my machine and reinstalled windows 7; the problem continues.

Specs: Intel iMac (early 2006, 2.0GHz, 2MB RAM, 240GB HD) running ONLY Windows 7 Professional, 32-bit (NOT through boot camp) and using a USB keyboard (Saitek Eclipse II.)

• Unplugging & reconnecting keyboard does NOT fix it.

• Connecting a different keyboard does NOT fix it. That one won't work, either.

• Drivers are up-to-date. Removing and reinstalling drivers does NOT fix it.

• Restarting the computer does NOT fix it. In fact, when the Windows logon screen appears the keyboard won't work and neither will the icon to pull up the on-screen keyboard. My mouse can click around just fine. I can only log onto a non-password protected account.

• Generally, logging into as different Windows user fixes it. I can then log back on to my main user account and continue work for a few hours until it happens again.

• Clearing my Chrome browsing data stopped the problem from recurring for a week or so.

• I have already REINSTALLED Windows 7 (not just a restore.) The problem returned after 2 days of use.

I use Avira free antivirus software, and repeated scans turn up nothing fishy.

I suspect it is related to something in Google Chrome because I used my google account to reload all my previous Chrome extensions, saved data, etc. (Chrome Extensions Installed: AdBlock, Better Google Tasks, DropBox, FB Photo Zoom, Google Mail Checker, StayFocusd.)

Any ideas? Any at all?