When sourcing DDR memory, you must first identify the generation required (DDR3, DDR4, or DDR5), as they are not backward compatible. Key performance indicators include Frequency (MHz) and CAS Latency (CL); higher frequencies and lower latencies signify better performance. For enterprise or server applications, ensure the modules support ECC (Error Correction Code) and are Registered (RDIMM) to maintain system stability. For consumer-grade electronics, Unbuffered DIMM (UDIMM) is standard. Always verify the Voltage requirements (e.g., 1.1V for DDR5 vs 1.2V for DDR4) to ensure compatibility with the target motherboard's power delivery system.