A systems administrator has performed a memory upgrade on a server. The server does not recognize the new memory. Which of the following is the MOST likely cause?

CPUs have a maximum addressable memory capacity determined by their architecture, number of memory channels, and chipset specifications - for example, a CPU rated for 256 GB maximum will not recognize any RAM installed beyond that limit. If an administrator installs more memory than the CPU supports, the system will silently cap recognition at the CPU's maximum and the additional DIMMs will appear absent. Verifying the CPU's official memory specification before purchasing an upgrade is the essential preventive step.

HDD firmware is entirely unrelated to RAM detection; the memory subsystem is controlled by the CPU and chipset, not storage firmware.

Incorrectly installed memory typically causes a complete POST failure or generates audible beep codes rather than allowing the system to boot while simply not recognizing the memory.

Defective original memory would cause pre-existing instability or errors in the prior configuration, not cause new replacement or additional memory to go unrecognized.