Memtest86 11.5.1000 – Free RAM Testing & Diagnostic Tool

PassMark’s MemTest86 is a trusted, comprehensive, and free memory diagnostic tool specifically designed to stress-test your computer’s RAM for errors. As a standalone program, it runs directly from a USB stick, allowing it to perform deep, rigorous tests on your system’s memory without interference. Use MemTest86 to detect faulty memory, troubleshoot system crashes, and ensure your PC performs optimally.

MemTest86 is a standalone diagnostic tool that operates independently of your operating system. You boot it from a USB flash drive to begin a series of rigorous tests on your computer’s RAM. The software utilizes sophisticated algorithms to verify that your memory can reliably store and retrieve data, ensuring there are no hidden faults that could cause system instability or crashes.

At its core, MemTest86 performs an intensive and comprehensive check of your computer’s RAM. It works by writing special diagnostic patterns to every memory address and then verifying the data’s integrity with a direct comparison. This rigorous process is designed to uncover even the most subtle memory faults. For those with a deeper interest in system performance, MemTest86 also offers advanced configurations that are tailored to specific chipsets. This feature is especially crucial for overclocking enthusiasts who need to ensure their high-performance systems remain stable under pressure.

PassMark Memtest86 Main Features:

• 13 different RAM testing algorithms
• DDR4 RAM (and DDR2 and DDR3) support
• XMP – high-performance memory profiles
• UEFI – The new graphical standard for BIOS
• 64bit – From version 5, MemTest86 is native 64bit code
• ECC RAM – support for error-correcting code RAM
• Secure boot – With MemTest86 being code-signed by Microsoft
• Graphical interface, mouse support, and logging of results to disk
• Foreign language support (Chinese, German, and more)
• Self-booting off USB, without needing DOS, Linux, or Windows
• Network (PXE) boot – Scalable, disk-less provisioning from a single PXE server

Unreliable RAM can lead to many issues, including data corruption, crashes, and unpredictable behavior. Faulty RAM is notoriously difficult to diagnose due to its intermittent and often subtle symptoms. MemTest86 can help identify faulty RAM or rule it out as a cause of system instability. As a result, it’s widely used by system builders, PC repair shops, overclockers, and PC manufacturers.

The number 86 following the MemTest part of the name refers to the original x86 CPU instruction set that all of today’s PCs use. This covers both 32-bit and 64-bit machines. (So there is no need for a future product called MemTest64.)

Free, Professional, or Site Edition

Since MemTest86 v5, the software has been available in a Free Edition or as a commercial Pro and Site Edition. The Pro Edition provides a range of additional features, including customizable reports and automation via a configuration file. Building on the Pro Edition, the Site Edition further enables scalable deployment of MemTest86 across the LAN via PXE boot.

MemTest86 supports booting from the newer UEFI platform.

When booting from UEFI, MemTest86 has access to additional services not available in BIOS, including:

• Native 64-bit support
• It no longer requires the PAE workaround to access more than 4GB of memory. (PAE = Physical Address Extension)
• Mouse support is available where the underlying UEFI system supports it. On older systems, a keyboard is still required.
• Improved USB keyboard support means that keyboards will now work on systems that do not correctly emulate IO Port 64/60. This includes support for Mac USB keyboards.
• Improved multi-threading support is available on systems with underlying UEFI functionality that allows for it.
• Reporting of detailed RAM SPD information. Timings, clock speeds, vendor names, and much more.
• Added support for writing to the USB drive where MemTest86 is running, enabling logging and report generation. Previous MemTest86 releases did not include disk support.
• Use of GPT. (GUID Partition Table)
• ECC RAM support (limited hardware support, ongoing development)
  • Detection of ECC support in both the RAM and the memory controller
  • Polling for ECC errors
  • Injection of ECC errors for test purposes. (limited hardware only)

• Support for DDR4 RAM (and associated hardware), including retrieval and reporting of DDR4-specific SPD details. This includes DDR4 RAM that supports Intel XMP 2.0 DDR4 RAM timings
• Option to disable CPU caching for all tests
• Support for Secure Boot.
• Speed improvements range from 10% to over 30%, particularly for tests #5, #8, and #9. These enhancements result from transitioning to native 64-bit code, eliminating the PAE paging hack, updating compilers, and implementing faster random number generation algorithms.
• The addition of two new memory tests leverages 64-bit data and SIMD instructions.
• Support for network PXE boot for scalable, diskless deployment to multiple targets