Memtest86+
Stand-alone memory tester for x86 and x86-64 architecture computers
...The tool can be booted directly via BIOS or UEFI, or through compatible bootloaders, making it highly flexible for troubleshooting unstable systems. It uses advanced testing algorithms specifically designed to detect intermittent, hard-to-find memory errors caused by cell interaction and hardware behavior. With ongoing development and community contributions, Memtest86+ remains a trusted solution for diagnosing memory-related system issues.