Odds probably the RAM was mismatched, and the BIOS did not choose conservative settings. Also could be voltage mismatch, and then your low voltage modules could fry (unlikely though).
There is something very wrong with the concept of 'runtime' macros. How is a 'runtime' macro any better than a function/procedure? TBH, I have no idea what a use case would be for a 'runtime' macro. A macro is generally a compile-time source transformation. If you need that at runtime, use EVAL.
Odds probably the RAM was mismatched, and the BIOS did not choose conservative settings. Also could be voltage mismatch, and then your low voltage modules could fry (unlikely though).