Simple Memory Tests
Simple memory tests test the first 2.5 GB of memory. To test all memory, run extended
memory tests.
Even though simple memory tests don’t test all memory, run these tests to detect
intermittent memory issues.
In AXD EFI tools, all memory tests (simple, multicore, and extended) are grouped under
Memory tests.
Note: The time required to complete memory tests correlates to the size of memory
being tested. These estimates are based on testing 1 GB of memory.
Test
Estimated completion time
Description
Address as Data
5 seconds
Tests memory using the
memory address as data.
Patterns
25 seconds
Tests memory using different
data patterns.
Marching Ones and Zeros
15 seconds
Tests memory by walking 1s and
0s up and down memory.
Knaizuk Hartmann
10 seconds
Tests memory using this
algorithm.
MOD3
30 seconds
Tests memory using this
algorithm.
March U
2 minutes
Tests memory using this
algorithm.
Random
15 seconds
Uses pseudo-random values.
Block Checkerboard 32
10 seconds
Alternates 32-bit words with all
1s and all 0s, and then with all
0s and all 1s.
Bit Checkerboard 32
10 seconds
Alternates bits with all 1s and
all 0s, and then with all 0s and
all 1s.
Sequential Byte Block 32
14 minutes
Fills all bytes sequentially with
patterns starting at 0x00 and
ending at 0xFF.
Walking One 32
5 minutes
Walks 1s up and down memory.
Walking Zero 32
5 minutes
Walks 0s up and down memory.
40
Appendix
AXD Tools Test Reference
Test
Estimated completion time
Description
Walking Spread Bit 32
5 minutes
Walks 0b01 up and then walks
0b10 down memory.
Walking Bit Flip 32
5 minutes
Alternates words with walking
1 and walking 0, and then
alternates with walking 0 and
walking 1.