Hi,
What troubleshooting steps have you tried so far?
**Method 1:**I would suggest you to perform a full system scan just to be safe.
Here is a link that will give you information on how to perform a full system scan:
http://www.microsoft.com/security/scanner/en-us/default.aspx
Note: Any data files that are infected may only be cleaned by deleting the file entirely, which means there is a potential for data loss.
Method 2: Un-install and re-install display adapter drivers.
Refer the following steps:
a) Click on Start, Right click on computer.
b) Click on properties, click on Device manager
c) Expand display adapter, Right click on the adapter option
d) Click on uninstall
e) Now go to your computer/ device manufacturer website, download the updated drivers and install them.
Method 3: Since it started after Windows update, perform System Restore, i.e. restore the computer to a date when it was working fine.
Step 1: System Restore: frequently asked questions:
http://windows.microsoft.com/en-US/windows7/System-Restore-frequently-asked-questions
Note: After System Restore, you will be offered Windows Updates again, install them one by one in clean boot and check if that helps.
Step 2: A clean boot helps to verify if any third party application service or startup item is causing this issue.
How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7:
http://support.microsoft.com/kb/929135
Note: After you have finished diagnosing, follow step 7 in the article to boot to normal startup.
You may also refer:
Updates: frequently asked questions: http://windows.microsoft.com/en-us/windows7/updates-frequently-asked-questions