Memtest86 is considered by the majority of the hardware testing community the number one application when it comes to defective RAM sticks. The answer to the question regarding the working state of the installed memory modules comes fast with Memtest86 and that is what matters the most besides the certainty of the verdict.
There are many good approaches for testing memory. However, many tests simply throw some patterns at memory without much thought or knowledge of memory architecture or how errors can best be detected. This works fine for hard memory failures but does little to find intermittent errors. BIOS based memory tests are useless for finding intermittent memory errors.
RAM chips consist of a large array of tightly packed memory cells, one for each bit of data. The vast majority of the intermittent failures are a result of interaction between these memory cells. Often writing a memory cell can cause one of the adjacent cells to be written with the same data. An effective memory test attempts to test for this condition. Therefore, an ideal strategy for testing memory would be the following:
Write a cell with a zero.
Write all of the adjacent cells with a one, one or more times.
Check that the first cell still has a zero.
It should be obvious that this strategy requires an exact knowledge of how the memory cells are laid out on the chip. In addition there are a never ending number of possible chip layouts for different chip types and manufacturers making this strategy impractical. However, there are testing algorithms that can approximate this ideal and MemTest86 does just this.
Starting from MemTest86 v5, the code was re-written to support booting from the newer UEFI platform. UEFI is able to provide additional services that is unavailable in BIOS, such as graphical, mouse and file system support.
UEFI or BIOS platform firmware
CD or USB Flash Drive
IMPORTANT: MemTest86 V5 (and later) images supports dual booting (UEFI/BIOS). On machines that don't support UEFI, the older V4 BIOS release of MemTest86 will be automatically booted.
Language : English
Home Page - http://www.memtest86.com