Windows 7 / Getting Started

Memory Failures

Because of the massive number of memory chips that hardware manufacturers produce and the high standards customers have for reliability, memory testing is a highly refined science. Different memory tests are designed to detect specific types of common failures, including the following:

  • A bit may always return 1, even if set to 0. Similarly, a bit may always return 0, even if set to 1. This is known as a Stuck-At Fault (SAF).
  • The wrong bit is addressed when attempting to read or write a specific bit. This is known as an Address Decoder Fault (AF).
  • A section of memory may not allow values to change. This is known as a Transition Fault (TF).
  • A section of memory changes when being read. This is called a Read Disturb Fault (RDF).
  • One or more bits lose their contents after a period of time. This is known as a Retention Fault (RF) and can be one of the more challenging types of failures to detect.
  • A change to one bit affects another bit. This is known as a Coupling Fault (CF) if the faulty bit changes to the same value as the modified bit, an Inversion Coupling Fault (CFin) if the faulty bit changes to the opposite value as the modified bit, or an Idempotent Coupling Fault (CFid) if the faulty bit always becomes a certain value (1 or 0) after any transition in the modified bit. This behavior can also occur because of a short between two cells, known as a Bridging Fault (BF).

Given these types of failures, it's clear that no single test could properly diagnose all the problems. For example, a test that wrote all 1s to memory and then verified that the memory returned all 1s would properly diagnose an SAF fault in which memory is stuck at 0. However, it would fail to diagnose an SAF fault in which memory is stuck at 1, and it would not be complex enough to find many BFs or CFs. Therefore, to properly diagnose all types of memory failures, Windows Memory Diagnostics provides several different types of tests.

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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