This 8GB RAM is 100% compatible with the Fujitsu CELSIUS R570-2 Power (D2628). You can populate the slots with ECC UDIMM (Unbuffered) or RDIMM (Registered) server memory. These two technologies cannot be used together in the system. When upgrading, you should know what memory is already installed or upgrade completely to RDIMM. To achieve good system performance, it is advisable to distribute the memory evenly across the memory slots and evenly across the CPUs. When using three identical memory modules per group of three slots and populating all slot groups, performance under peak loads can be up to three times faster than with a single module in each of the three slot groups. The different groups of three slots do not need to have the same capacities. If more than one CPU is present, the memory should be identical per CPU (mirrored to the other CPU). Only the memory slots where the respective CPU is present can be used.