I got those errors few times within last 6 days when either opening new programs or ATI control center or simply just closing programs i.e.: media center. 1. The instruction of "0x00ed0fd8" referenced memory at "0x5F08001e". The memory could not be read. 2. The instruction of "0x00fe0f7f" referenced memory at "0x5F08001e". The memory could not be read. 3. The instruction of "0x01750039" referenced memory at "0x5F08001e". The memory could not be read. 4. The instruction of "0x049e0076" referenced memory at "0x5F08001e". The memory could not be read. Then I got this little window with the following message" This shut down instruction by TN AUTHORITY\system System 321 service.exe. Terminated expectantly with start code -1073741819. Then the system shuts down and reboots itself. Thank you for your help in advance. Drewski