How to Check RAM Health on Windows 11 (Built-In Tool + MemTest86 Guide)

Your PC randomly freezes. Apps crash without warning. You get a Blue Screen of Death that mentions something about memory. Or maybe your computer just feels slower than it should.

These are classic symptoms of failing RAM. The tricky part is that RAM failure is gradual — it doesn’t just stop working one day. It develops small errors that cause random, seemingly unrelated problems. That’s why regular RAM health checks matter, especially if your PC is more than a couple of years old.

Windows 11 has a built-in tool for this. But here’s the frustrating part: it hides the test results in Event Viewer, and most people never find them. They run the diagnostic, the PC reboots, and they see… nothing. No popup, no notification. They assume their RAM is fine when they never actually saw the results.

Let me show you how to run the test properly and where to find those hidden results.

Signs Your RAM Might Be Failing

Before running any test, here’s what RAM failure actually looks like:

• Random Blue Screens (BSODs) — especially with stop codes like MEMORY_MANAGEMENT, IRQL_NOT_LESS_OR_EQUAL, or PAGE_FAULT_IN_NONPAGED_AREA
• Apps crash randomly — not the same app every time, but different apps at different times
• PC freezes and becomes unresponsive — mouse and keyboard stop working, you have to hard reboot
• Files get corrupted — you save a file and when you open it again, it’s damaged
• PC gets slower over time within a single session (fine after fresh boot, progressively slower)

If you’re experiencing any of these, testing your RAM should be step one.

Method 1: Windows Memory Diagnostic (Built-In)

Running the Test

1. Press Win + R, type mdsched.exe, press Enter
2. Click “Restart now and check for problems (recommended)”
3. Save all your work first — your PC will reboot immediately

Your PC restarts into a blue screen that says “Windows Memory Diagnostics Tool.” The test starts automatically.

Switching to Extended Mode

By default, the tool runs in Standard mode. For a more thorough test:

1. Press F1 while the scan is running
2. Under Test Mix, select Extended (arrow keys to navigate, Tab to switch sections)
3. Under Pass Count, change from 2 to 4 or more
4. Press F10 to apply

Extended mode takes significantly longer but catches more errors.

Finding the Hidden Results

After the test completes, your PC reboots back into Windows. And here’s where everyone gets lost — there’s no popup showing the results. Windows says it will show a notification, but it often doesn’t.

Here’s where the results actually are:

1. Press Win + R, type eventvwr.msc, press Enter
2. In the left panel, expand Windows Logs
3. Click on System
4. In the right panel, click Find…
5. Type MemoryDiagnostics-Results and click Find Next

You’ll find an entry like:

“The Windows Memory Diagnostic tested the computer’s memory and detected no errors.”

Or, if there are problems:

“The Windows Memory Diagnostic tested the computer’s memory and detected hardware errors. Contact your computer manufacturer.”

If you see errors, your RAM needs attention. If no errors were found, your RAM passed the basic test — but read on for why you might want a second opinion.

Method 2: MemTest86 (More Thorough)

Windows Memory Diagnostic is good for quick checks, but it doesn’t catch everything. MemTest86 is the industry-standard RAM testing tool used by PC technicians and hardware manufacturers. It runs outside of Windows, giving it direct access to all your RAM.

Why MemTest86 Is Better

• Tests all available RAM (Windows Memory Diagnostic can’t test the RAM that Windows itself is using)
• Runs 13 different test algorithms vs. the built-in tool’s limited set
• Can run for hours to catch intermittent errors that only appear under sustained stress
• Produces a detailed HTML report you can save

How to Use MemTest86

1. Download: Go to memtest86.com → click “Free Download” → download the USB image
2. Create bootable USB: Extract the zip file → run the included imageUSB.exe → select your USB drive → click Write
3. Boot from USB: Restart your PC → enter BIOS/Boot Menu (usually F2, F12, Del, or Esc during startup) → select the USB drive
4. Run the test: MemTest86 starts automatically. Let it run for at least 4 passes (4 complete cycles through all tests). For best results, run it overnight.
5. Check results: After completion, MemTest86 shows a summary. Zero errors = healthy RAM. Any errors = faulty RAM.

How Long Does MemTest86 Take?

Let it run while you sleep. Intermittent RAM errors might only appear after multiple passes.

What to Do If Errors Are Found

Isolate the Faulty Stick

If you have multiple RAM sticks (most PCs have 2 or 4):

1. Turn off your PC and unplug it
2. Remove all RAM sticks except one
3. Run MemTest86 again on just that one stick
4. If no errors → that stick is fine. Put it aside and test the next one
5. The stick that produces errors is the faulty one

Replace or RMA

• If your RAM is under warranty, contact the manufacturer (Corsair, G.Skill, Kingston, etc.) for an RMA (Return Merchandise Authorization)
• If out of warranty, replace the faulty stick with the same speed and type — check your motherboard manual for compatible RAM specifications
• Always buy RAM in matched kits (pairs) for best compatibility

If No Errors Are Found But PC Still Crashes

Your crashes are probably caused by something else:

• Overheating → check CPU/GPU temperatures with HWMonitor
• Failing SSD/HDD → check drive health with CrystalDiskInfo
• Driver issues → update or roll back GPU drivers
• Unstable overclock → revert to default speeds
• Windows corruption → run sfc /scannow and DISM /Online /Cleanup-Image /RestoreHealth in admin Command Prompt

Windows 11’s New Automatic RAM Check (2025 Feature)

Starting with Windows 11 build 26220 (25H2), Microsoft is testing a new feature: automatic RAM diagnostics after a BSOD. If your PC crashes, Windows will suggest running a quick memory scan on the next reboot. This takes about 5 minutes and runs automatically.

This feature is currently rolling out to Windows Insiders. If you see a notification after a crash suggesting a memory scan, say yes — it’s the new built-in check.

Frequently Asked Questions

How often should I check my RAM?

For most people, once every 6 months is sufficient. Check immediately if you start experiencing random crashes, BSODs, or file corruption. Also check after installing new RAM or after any hardware changes.

Does more RAM help if my existing RAM is healthy?

If your existing RAM is healthy but your PC is slow, the bottleneck might be RAM amount, not RAM health. Open Task Manager (Ctrl+Shift+Esc) → Performance tab → Memory. If usage is consistently above 80%, adding more RAM will help. If it’s below 60%, more RAM won’t make a noticeable difference.

Can software cause RAM-like symptoms?

Yes. Malware, memory-leaking applications, and driver bugs can cause crashes that look identical to RAM failures. Always run a RAM test before blaming hardware — it could save you from buying new RAM you don’t need.

Is there a quick way to check RAM speed and type without opening my PC?

Yes. Open Task Manager → Performance tab → Memory. It shows your total RAM, speed (e.g., 3200 MHz), form factor (DIMM or SODIMM), and how many slots are used. For more detail, open Command Prompt and run: wmic memorychip get capacity, speed, manufacturer, partnumber

Check Your RAM Before Blaming Everything Else

RAM failures cause the most confusing symptoms in computing — random crashes that seem to have no pattern. The 5-minute Windows Memory Diagnostic test (plus knowing where to find the results in Event Viewer) can save you hours of troubleshooting the wrong thing. If the basic test passes but crashes continue, MemTest86 overnight is the gold standard.

Last updated: February 2026 | Tested on Windows 11 24H2/25H2 | MemTest86 v11.2