Recommended Free Tools
Test the memory before buying replacement RAM. If Windows still starts, run Windows Memory Diagnostic first. If crashes continue or you need a test that runs outside the installed operating system, create a bootable MemTest86 USB and let its configured test sequence complete. An error identifies a problem somewhere in the memory system—not automatically one defective RAM stick—so confirm the cause by returning settings to conservative defaults and testing modules and slots methodically.
Why testing comes before replacement
Unstable memory can produce blue screens, application crashes, failed installations, corrupted files and random restarts. Those symptoms can also come from a motherboard slot, a memory-controller or CPU issue, incompatible modules, or an aggressive memory profile. Replacing a kit on symptoms alone can waste money and may leave the real fault untouched.
As an Amazon Associate I earn from qualifying purchases.
A diagnostic gives you a reproducible starting point. A completed run with no detected errors is evidence that the configured tests passed under those conditions; it is not a guarantee that every intermittent fault has disappeared. A completed run with an error is a reason to investigate the complete memory subsystem before ordering parts.
Quick wins for a faster PC:
Repair Windows errors before they cause bigger problemsFix Now →Scan for outdated or missing drivers - takes under a minuteDriver Scan →A practical decision path
- Windows works reliably enough to launch a test: run Windows Memory Diagnostic and retrieve its result in Event Viewer.
- The first check is clean but crashes continue, or Windows is too unstable: use a standalone MemTest86 boot test.
- MemTest86 reports an error: restore conservative memory settings, repeat the test, then isolate removable modules and slots.
- The failure follows one module across different slots: that module becomes the leading suspect. Arrange warranty service or replacement only after checking the system’s compatibility requirements.
- The failure stays with one slot or only appears with a particular combination: investigate the motherboard, firmware settings and module compatibility instead of replacing a single stick immediately.
Run Windows Memory Diagnostic
Windows Memory Diagnostic is built into Windows and is a convenient first check when the computer can still run normally enough to schedule a restart. Microsoft lists it as a memory check in its guidance for IRQL-related stop errors. The result is recorded in Event Viewer rather than displayed as a detailed report on the desktop.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
Start the test
- Save open work and close applications.
- Open the Start menu and search for Windows Memory Diagnostic.
- Open the utility and choose Restart now and check for problems if you can restart immediately. Choose the option to check at the next restart if you need to save work first.
- Allow the computer to reboot. The diagnostic runs before Windows loads and shows its progress on a blue test screen.
- Wait for the check to finish and for Windows to start again. Do not power off the computer while the test is running.
Find the result in Event Viewer
Microsoft documents this path for the result: Applications and Services Logs > Microsoft > Windows > MemoryDiagnostics-Results > Debug. Open Event Viewer, expand each folder in that order, and select the most recent result event. Record whether errors were reported and the date and time of the run. If no event appears, rerun the test and check that you are viewing the Debug log rather than a similarly named channel.
Windows Memory Diagnostic is useful as a quick, built-in screen, but a clean message should be treated as the result of that run and configuration. If the machine remains unstable, continue with an independent boot test or broader hardware troubleshooting.
Use MemTest86 as a standalone follow-up
MemTest86 starts from USB before the installed operating system, removing Windows drivers and applications from the test environment. The official download page lists MemTest86 11.7 Build 1000; its V11.7 image requires a computer with UEFI firmware. PassMark directs computers without UEFI to the older V4 release instead. Check the firmware mode and select the appropriate official download at https://www.memtest86.com/download.htm.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
What you need
- A spare USB flash drive with capacity greater than 1 GB. The imaging process erases the selected drive, so copy off anything you need before beginning.
- Access to the computer’s firmware or one-time boot menu. The key varies by manufacturer; consult the motherboard or computer manual if the startup screen does not identify it.
- Enough time for the configured sequence to finish. An interrupted run is not equivalent to a completed clean pass.
Create the bootable USB in Windows
- Download the MemTest86 package from the official page.
- Extract the downloaded archive to a folder you can find easily.
- Insert the spare USB drive. Confirm its drive letter and contents; the next step will erase it.
- Run the included imageUSB utility from the extracted package.
- Select the correct USB device in imageUSB, choose the option to write the MemTest86 image, and start the operation.
- Accept the warning only after verifying that the selected drive is the disposable test drive. PassMark’s instructions at https://www.memtest86.com/tech_creating-window.html describe this workflow and the data-erasure warning.
- Safely eject the drive after imageUSB reports completion, or leave it inserted for the next restart.
Boot from the USB
- Restart with the MemTest86 drive connected.
- Open the one-time boot menu during startup, or enter firmware setup and move the USB device ahead of the internal drive. The required key differs among systems; PassMark’s boot instructions are at https://www.memtest86.com/tech_booting-memtest.html.
- Select the UEFI MemTest86 entry when using the V11.7 image. If the computer has no UEFI support, stop and obtain the compatible older V4 release rather than assuming the V11.7 image will boot.
- Leave the default test selection in place for the first diagnostic unless you have a specific reason to change it.
- Start the run and let the configured sequence complete. Photograph or write down any error count, test number, failing address, and the module or slot arrangement.
Interpret MemTest86 results correctly
PassMark defines the result labels in its documentation at https://www.memtest86.com/tech_test-result.html. Use the exact status rather than treating any screen message as a verdict.
| Status | What it means | What to do next |
|---|---|---|
| PASS | All configured tests completed and no errors were detected. | Use it as evidence about this run and setup. If symptoms continue, keep troubleshooting instead of declaring every memory fault ruled out. |
| FAIL | All configured tests completed and at least one error was detected. | Investigate settings, compatibility, modules and slots before buying parts. |
| INCOMPLETE PASS | The configured sequence did not finish, and no error was recorded before it stopped. | Repeat the test and allow the full sequence to finish; this is not a completed clean pass. |
| INCOMPLETE FAIL | The sequence did not finish and an error was recorded. | Repeat under conservative settings, then begin isolation while preserving the error details. |
The number of passes, test selection and run conditions matter. A single completed run can miss an intermittent problem, while a repeatable error under the same conditions is stronger evidence. Keep a record of firmware settings and which modules were installed for each run so that results can be compared rather than guessed at.
What a memory-test error actually proves
An error proves that the test detected incorrect behavior in the tested memory system. It does not by itself prove that a particular DIMM is defective. PassMark explains at https://www.memtest86.com/troubleshooting.htm that MemTest86 also exercises the CPU, caches and motherboard, and that incompatibility or marginal operating conditions can produce errors.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Errors can change between runs or after a setup change. For example, enabling an overclocked memory profile, mixing kits, using an unsupported speed or running with marginal voltage can make a previously stable configuration fail. Conversely, a one-time clean run does not prove that an intermittent issue is gone. Treat the result as a trigger for controlled diagnosis.
Reset aggressive settings before judging the hardware
If the firmware uses an overclocked memory profile or manually tuned timings, return it to the motherboard’s conservative or default memory settings before retesting. The exact label varies by firmware; it may be called a memory profile, performance profile or an overclocking preset. Do not copy settings from another system. Save the current configuration if the firmware offers that option, then load defaults, confirm the intended memory capacity is detected, and rerun the same test.
If errors disappear at default settings but return when a profile is enabled, the evidence points to a settings, voltage, speed or compatibility limit rather than automatically to a dead module. Decide whether the performance profile is worth keeping only after checking the motherboard and CPU documentation for supported memory specifications.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Isolate modules and slots methodically
Module isolation is the most useful next step when the computer has removable memory and you are comfortable opening it. Shut down fully, disconnect power, observe electrostatic-safety precautions, and consult the computer or motherboard manual for the correct removal procedure. Do not force a module or work inside a system that is still powered.
- Record the original arrangement, including which stick occupied each labeled slot.
- Install one module in the slot recommended by the manual for a single-DIMM configuration.
- Run the same MemTest86 configuration to completion and record the status and error details.
- Repeat with the other module, keeping the slot and settings the same.
- If one module fails, move that module to another supported slot and test again.
- If a module passes in one slot but fails in another, test a known-good module in both slots to separate a slot or board problem from a module problem.
- Only after individual tests are understood should you reinstall the full set and check whether the combination itself causes errors.
A failure that follows one stick across multiple supported slots is stronger evidence against that stick. A failure that remains tied to one slot, or appears only when two modules are installed together, points toward the board, firmware settings or compatibility. This inference helps rank suspects; it is not an absolute component-level guarantee.
Free tools Windows power users keep installed
One-click scans. No signup required.
Check compatibility before ordering RAM
Capacity alone is not a compatibility specification. Before purchasing anything, identify the exact computer model or motherboard revision and consult its documentation for supported memory type, generation, module capacity, slot population, speed and any firmware requirements. Desktop and laptop modules are not interchangeable, and physically fitting a module does not establish electrical or firmware compatibility.
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
- Match the memory generation and form factor specified for the system.
- Confirm the maximum capacity per slot and total supported capacity.
- Check whether the board expects a particular slot order for one or two modules.
- Avoid combining unrelated kits when the manual or manufacturer support information does not list the combination as supported.
- Keep the failed module and test records until the replacement has passed a complete diagnostic.
If the module is under warranty, the test records, error photographs and module/slot results can make a warranty claim more useful. If the evidence implicates the motherboard slot or compatibility instead, replacing RAM alone may not solve the instability.
If tests pass but the computer still crashes
Do not stop at the word “PASS” when the original symptom is still present. First verify that the run actually completed, that the test settings were appropriate, and that the current module arrangement matches the configuration that was failing. Then consider other causes such as storage corruption, overheating, power delivery, firmware bugs, drivers or a failing CPU or motherboard.
Repeat the test after a cold start and after restoring defaults if the first run was performed with a performance profile. Compare results rather than changing several variables at once. If Windows reports memory-related stop codes but both a built-in check and a completed standalone run remain clean, preserve crash details and broaden the investigation instead of repeatedly buying memory.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
Windows Memory Diagnostic vs. MemTest86
| Factor | Windows Memory Diagnostic | MemTest86 |
|---|---|---|
| Where it runs | Scheduled from Windows, then runs during reboot before Windows loads. | Boots independently from USB, outside the installed operating system. |
| Setup | Built in; no separate media is required. | Requires a spare USB drive larger than 1 GB and image creation. |
| Result location | Event Viewer at Applications and Services Logs > Microsoft > Windows > MemoryDiagnostics-Results > Debug. | Displayed by the boot utility and available through its result/report screens. |
| Firmware requirement | Uses the computer’s existing Windows and firmware path. | MemTest86 V11.7 requires UEFI; non-UEFI computers need the older V4 release. |
| Best use | Fast first check when Windows remains usable. | Independent follow-up, repeatable module/slot testing and systems too unstable for a dependable Windows session. |
| Limit | A clean result applies to that run and does not explain every intermittent crash. | An error can involve CPU, cache, motherboard, settings or compatibility, not only a RAM stick. |
Neither tool should be treated as universally conclusive in isolation. The strongest practical diagnosis combines a completed test with controlled settings, repeat runs and module/slot isolation.
A replacement decision checklist
- Did the test sequence finish, rather than stop partway through?
- Was the result repeatable under conservative, documented settings?
- Did the error follow one module when tested in more than one supported slot?
- Did another known-good module behave differently in the suspected slot?
- Have you checked the exact motherboard or computer memory specifications?
- Have you ruled out a profile, speed, voltage or mixed-kit compatibility issue?
Replace or submit a warranty claim when repeatable errors continue at appropriate default settings and the evidence follows a specific module. Choose a module or kit that matches the exact system documentation, install it in the prescribed slots, and run a complete diagnostic after installation. If the evidence instead follows a slot or a particular combination, pursue motherboard, firmware or compatibility troubleshooting before spending on another RAM kit.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
