If the submitter was right, the problem was that the area of memory where a power controller's registers were mapped was not marked as "reserved", so it is enti

If the submitter was right, the problem was that the area of memory where a power controller's registers were mapped was not marked as "reserved", so it is entirely reasonable for memtest to poke at that memory. In other words, the failure is actually in the laptop's BIOS that provides the memory map.