A-Tech 32GB DDR5 4800 ECC UDIMM 2Rx8 HP/HPE P64339-B21 Server RAM

32GB DDR5 ECC UDIMM for HP/HPE Servers

This 32GB DDR5 4800 module is built as a direct replacement for the HP/HPE P64339-B21 part number. It targets administrators who need to expand memory capacity in compatible ProLiant or Apollo platforms that accept unbuffered ECC UDIMMs. The single-rank 2Rx8 organisation and standard 1.10V operation match the original specification. Buyers who require registered RDIMMs or higher-density 64GB modules should verify their system documentation before ordering.

Installation is a standard DIMM insertion

Align the 288-pin module with the slot key notch, press firmly until the retention clips click, and follow the server manual for correct channel population order. The most common issue is mixing this unbuffered ECC stick with registered memory, which prevents the system from posting. Another frequent error is leaving empty slots between populated channels, which can disable the new capacity. No heat spreader is fitted, so airflow clearance is not a concern.

ECC unbuffered 2Rx8 at DDR5 4800 decides fit

The module runs at PC5-38400 with a CAS latency of 40 and presents a 2Rx8 rank structure to the memory controller. These three parameters — ECC type, buffer state and rank organisation — must match the platform's qualified vendor list exactly; a mismatch in any one will cause the server to reject the DIMM or run it at a reduced speed. Confirm the part number P64339-B21 appears in your hardware maintenance guide before purchase.