When sourcing RAM, you must prioritize DDR generation (DDR4 vs. DDR5), as they are not backward compatible. Key performance metrics include Frequency (MHz) and CAS Latency (CL); higher frequencies and lower latencies command higher prices but offer superior performance. For enterprise or server-grade needs, ensure the modules support ECC (Error Correction Code) to prevent data corruption. Always verify the chip brand (e.g., Samsung, SK Hynix, Micron), as the quality of the DRAM die directly impacts the product's stability and overclocking potential.