This 8GB RAM is 100% compatible with the Tyan S5545 (S5545AG2NR). Information regarding memory configuration: The following technical specifications should be noted in advance: A higher memory clock of the memory module automatically adjusts to the clock set by the system. This can especially be the case with larger capacities. Non-ECC or ECC (Error-Correction-Code) RAM can be installed in the device. Modules labeled ECC have error correction. Non-ECC memory modules cannot be mixed with ECC memory. If a memory upgrade is to be made with the already existing RAM, it must be checked which memory technology (non-ECC / ECC) is present.