What components does Memtest86 test?

Memtest86 primarily tests the computer's RAM (Random Access Memory) for errors by performing a series of comprehensive diagnostic patterns and algorithms. It checks for various types of memory issues, including bit flip errors, address line failures, and data bus errors. The tool can also assess memory controller functionality and compatibility with the motherboard. Overall, Memtest86 is essential for identifying faulty memory that could lead to system instability and crashes.