Windows 7 / Getting Started

How to Use Windows Memory Diagnostics

Memory problems are one of the most common types of hardware problem. Memory problems can prevent Windows from starting and cause unpredictable Stop errors when Windows has started. Because memory-related problems can cause intermittent failures, they can be difficult to identify.

Fortunately, Windows includes Windows Memory Diagnostics, an offline diagnostic tool that automatically tests your computer's memory. Windows Memory Diagnostics tests your computer's memory by repeatedly writing values to memory and then reading those values from memory to verify that they have not changed. To identify the widest range of memory failures, Windows Memory Diagnostics includes three different testing levels:

  • Basic Basic tests include:
    • MATS+
    • INVC
    • SCHCKR (which enables the cache)
  • Standard All basic tests, plus:
    • LRAND
    • Stride6 (which enables the cache)
    • CHCKR3
    • WMATS+
    • WINVC
  • Extended All standard tests, plus:
    • MATS+ (which disables the cache)
    • Stride38
    • WStride-6
    • CHKCKR4
    • WCHCKR3
    • ERAND
    • Stride6 (which disables the cache)
    • CHCKR8

Although the specifics of each of these tests are not important for administrators to understand, it is important to understand that memory testing is never perfect. Failures are often intermittent and may occur only once every several days or weeks in regular usage. Automated tests such as those done by Windows Memory Diagnostics increase the likelihood that a failure can be detected; however, you can still have faulty memory while Windows Memory Diagnostics indicates that no problems were detected. To minimize this risk, run the Extended tests and increase the number of repetitions. The more tests you run, the more confident you can be in the result. If you have even a single failure, it indicates faulty memory.

After Windows Memory Diagnostics completes testing, the computer will automatically restart. Windows will display a notification bubble with the test resultsc and you can view events in the System Event Log with the source MemoryDiagnosticsResults (Event ID 1201).

If you do identify a memory failure, it is typically not worthwhile to attempt to repair the memory. Instead, you should replace unreliable memory. If the computer has multiple memory cards and you are unsure which card is causing the problem, replace each card and then rerun Windows Memory Diagnostics until the computer is reliable.

If problems persist even after replacing the memory, the problem is caused by an outside source. For example, high temperatures (often found in mobile PCs) can cause memory to be unreliable. Although computer manufacturers typically choose memory specifically designed to withstand high temperatures, adding third-party memory that does not meet the same specifications can cause failure. Besides heat, other devices inside the computer can cause electrical interference. Finally, motherboard or processor problems may occasionally cause memory communication errors that resemble failing memory.

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In this tutorial:

  1. Troubleshooting Hardware, Driver, and Disk Issues
  2. Windows 7 Improvements for Hardware and Driver Troubleshooting
  3. Windows Troubleshooting Platform
  4. Built-in Troubleshooting Packs
  5. Windows Troubleshooting Platform Components
  6. Creating Custom Troubleshooting Packs
  7. Running Troubleshooting Packs Remotely
  8. Windows 7 Reliability Monitor
  9. Windows 7 Resource Monitor
  10. Windows Memory Diagnostics
  11. Disk Failure Diagnostics
  12. Self-Healing NTFS
  13. Improved Driver Reliability
  14. Improved Error Reporting
  15. The Process of Troubleshooting Hardware Issues
  16. How to Troubleshoot Problems That Prevent Windows from Starting
  17. How to Troubleshoot Problems Installing New Hardware
  18. How to Troubleshoot Problems with Existing Hardware
  19. How to Troubleshoot Unpredictable Symptoms
  20. How to Diagnose Hardware Problems
  21. How to Use Device Manager to Identify Failed Devices
  22. How to Check the Physical Setup of Your Computer
  23. How to Check the Configuration of Your Hardware
  24. How to Verify That System Firmware and Peripheral Firmware Are Up to Date
  25. How to Test Your Hardware by Running Diagnostic Tools
  26. How to Simplify Your Hardware Configuration
  27. How to Diagnose Disk-Related Problems
  28. How to Use Built-In Diagnostics
  29. How to Use Reliability Monitor
  30. How to Use Event Viewer
  31. How to Use Data Collector Sets
  32. How to Use Windows Memory Diagnostics
  33. Memory Failures
  34. How Windows Automatically Detects Memory Problems
  35. How to Schedule Windows Memory Diagnostics
  36. How to Start Windows Memory Diagnostics When Windows Is Installed
  37. How to Start Windows Memory Diagnostics from the Windows DVD
  38. How to Configure Windows Memory Diagnostics
  39. How to Troubleshoot Disk Problems
  40. How to Prepare for Disk Failures
  41. How to Use ChkDsk
  42. ChkDsk Examples
  43. ChkDsk Syntax
  44. How to Use the Graphical ChkDsk Interface
  45. How to Determine Whether ChkDsk Is Scheduled to Run
  46. ChkDsk Process on NTFS Volumes
  47. How to Use the Disk Cleanup Wizard
  48. How to Disable Nonvolatile Caching
  49. How to Troubleshoot Driver Problems
  50. How to Find Updated Drivers
  51. How to Roll Back Drivers in Windows 7
  52. How to Use Driver Verifier
  53. How to Use the File Signature Verification
  54. How to Use Device Manager to View and Change Resource Usage
  55. How to Use Windows 7 System Restore
  56. How to Troubleshoot USB Problems
  57. How to Solve USB Driver and Hardware Problems
  58. Understanding USB Limitations
  59. How to Identify USB Problems Using Performance Monitor
  60. How to Examine USB Hubs
  61. How to Troubleshoot Bluetooth Problems
  62. Troubleshooting Tools
  63. DiskView
  64. Handle
  65. Process Monitor