How to Run the Memory Diagnostics Tool in Windows 7:
1. Click the Start button in Windows 7 --> the Control Panel (All Items View) --> the Administrative Tools icon --> Memory Diagnostics Tool.
2. The "windows Memory Diagnostics Tool" window will pop up, select the Restart now and check for problems option.
3. The computer will now restart, and windows will start to check for memory problem. This might take several minutes. By default Windows Memory Diagnostic Tool will run the Standard test.
4. When the test is finished running, the computer will be automatically restarted.