Install one RAM module and test with Memtest86+ version 5.31b ( https://www.memtest.org/ ) for 8 or more passes > take pictures with a camera or smartphone camera > post images into the thread
Test all RAM modules in the same DIMM for 8 or more passes.
If the single RAM module and DIMM pass then test every DIMM with the same RAM module.
If the single RAM module and DIMM fail then test another RAM module in all DIMM.
When the above steps have completed all 4 DIMM should have been tested.
Make sure there are at least 8 passes / test.
The testing is done not by time but by passes.
The more passes the better the testing conditions.
There are a significant number of false negatives if fewer than 8 passes are made.
A false negative is a test pass when there is malfunctioning RAM.
Memtest86+ version 5.31b testing takes approximately 1 - 2 hours /GB RAM
https://www.memtest.org/
Just 1 error is a fail and you can abort testing.
A significant portion of the testing can be performed overnight.
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