I have a Inspiron14 R.  It has been generally stable. Now the screen can be unstable - by that I mean  text jumps up a line or two then returns.  I have keyboard icon flashing on and off in the taskbar.  The system is too busy to launch most applications.  One window can be stable and another unreadable at the same time.  Here is what I have found:

• Several hardware diagnostic tests have found no trouble.  
• Event viewer has a long list of Win32k errors - numbers 263 and 264. 
• I tried using a three week old  restore point to no avail. 
• If I either roll back the video driver or update the driver it can stabilize until I reboot. I did go to the Dell site and update 3 drivers shortly before the problem started, and I think the the video driver was among them, but I did not record which drivers I downloaded. 
• When experiencing the problem, the performance monitor shows heavy CPU usage, even with no applications running.  When I can stabilize the system the CPU usage drops tremendously.

I have been troubleshooting this for about a week.   Any ideas?