Memory errors and how to test RAM

What Are Memory Errors?

Your computer's RAM (Random Access Memory) temporarily stores data that programs are actively using. When RAM develops errors - from physical damage, manufacturing defects, or electrical problems - your computer can crash, freeze, show corrupted graphics, or display blue screens with errors like MEMORY_MANAGEMENT or PAGE_FAULT_IN_NONPAGED_AREA.

Memory errors are often random and inconsistent, making them tricky to diagnose. You might be able to use your computer for hours without issues, then suddenly it crashes. The key is running proper memory tests to confirm if RAM is the problem.

Quick Test: Windows Memory Diagnostic

Windows has a built-in memory tester that can find most RAM problems. Press Windows + R, type mdsched.exe, and press Enter. Select "Restart now and check for problems." Your computer will restart and run memory tests for 10-20 minutes.

When complete, Windows will restart normally. Check the results by opening Event Viewer (Windows + X > Event Viewer), navigating to Windows Logs > System, and looking for MemoryDiagnostics-Results. If errors were found, your RAM needs to be replaced.

Signs of Bad RAM

Watch for these symptoms that suggest memory problems:

• Random blue screens, especially with memory-related error codes
• Computer freezes during normal use or when opening programs
• Files become corrupted for no reason
• Programs crash with "access violation" or similar errors
• Weird visual glitches or artifacts on screen
• Beeping sounds when starting the computer (usually 2-3 beeps)
• Windows installation fails repeatedly at random points

Detailed Testing Steps

Method 1: Run Extended Memory Diagnostic

For more thorough testing than the quick test:

1. Press Windows + R, type mdsched.exe, and press Enter
2. Select "Restart now and check for problems"
3. When the blue memory diagnostic screen appears, press F1 for Options
4. Change Test Mix to Extended
5. Change Pass Count to at least 2 (more is better but takes longer)
6. Press F10 to apply and start testing
7. Let it run - Extended tests can take several hours
8. Check results in Event Viewer after restart

Method 2: Use MemTest86 (Most Thorough)

MemTest86 is the gold standard for RAM testing and can find errors Windows Memory Diagnostic misses.

1. Download MemTest86 from memtest86.com (free version is fine)
2. Create a bootable USB drive using their tool
3. Restart your computer and boot from the USB (press F12, F2, or Del during startup to access boot menu)
4. MemTest86 will start automatically
5. Let it run at least one complete pass (takes 1-4 hours depending on RAM amount)
6. If any errors appear in red, your RAM is faulty
7. For best results, run 4+ passes overnight

Method 3: Test Individual RAM Sticks

If you have multiple RAM sticks, test each one individually to find the faulty one.

1. Shut down and unplug your computer
2. Open the case (consult your manual for location)
3. Remove all but one RAM stick
4. Boot up and run Windows Memory Diagnostic or MemTest86
5. If no errors appear, shut down and swap in a different stick
6. Test each stick individually
7. The stick that shows errors is the faulty one - replace only that stick

This saves money since you only need to replace the failed stick, not all your RAM.

Method 4: Reseat Your RAM

Sometimes RAM isn't faulty - it's just not seated properly in its slot. This can happen from vibration, moving the computer, or dust buildup.

1. Shut down and unplug your computer
2. Touch a metal part of the case to discharge static electricity
3. Open the case and locate your RAM sticks
4. Press down the retention clips on both ends of each RAM stick
5. Carefully remove each stick
6. Gently clean the gold contacts with a soft cloth (no liquids)
7. Clean any dust from the RAM slots with compressed air
8. Firmly push each stick back into its slot until clips snap into place
9. Close the case, plug in, and test

Method 5: Check for Overheating

RAM can develop errors when it overheats. This is less common than physical damage but worth checking.

1. Download HWMonitor or similar hardware monitoring software
2. Run it while using your computer normally
3. Check temperatures of all components
4. CPU should stay under 80-85°C, GPU under 85-90°C
5. If everything is running hot, your case airflow is inadequate
6. Clean out dust, add fans, or improve cable management for better airflow

Fixing Memory Errors

If RAM Is Faulty

Bad RAM cannot be repaired - it must be replaced. Here's how:

1. Identify your RAM type: Press Windows + Pause/Break, or check System in Settings
2. Note the RAM type (DDR4, DDR5), speed (3200MHz, etc.), and how much you have
3. Purchase matching replacement RAM (same type and speed)
4. Shut down, unplug, and open your case
5. Remove the faulty stick by pressing the retention clips
6. Insert the new stick, pressing firmly until clips snap
7. Boot up and verify Windows recognizes the full RAM amount

For best performance, use matching pairs of RAM sticks. If replacing one stick, try to match the brand, speed, and timings of your existing RAM.

If RAM Tests Clean

If memory tests don't find errors but you still have crash symptoms:

• Test your hard drive with CrystalDiskInfo - drive failures mimic RAM errors
• Check for overheating - sustained high temperatures cause instability
• Update your motherboard BIOS - sometimes fixes memory compatibility issues
• Test with different RAM if possible to rule out motherboard slot problems
• Run sfc /scannow to check for Windows file corruption