Introduction

RAM speed is often misunderstood. It's not just about the large number (frequency); the timings (latency) play an equally critical role in how quickly your system can access stored data.

Frequency (MHz)

Frequency, measured in Megahertz (MHz), dictates how many cycles the RAM completes per second. Higher frequency means faster data transfer rates. For current Intel/AMD platforms, 6000MHz is often the sweet spot for price-to-performance.

CAS Latency (CL)

CAS Latency (CL) measures the delay, in clock cycles, between the memory controller requesting data and the RAM module actually starting to send it. A lower CL number is better.

Calculating True Latency

True Latency (in nanoseconds) is calculated by: (CL / Frequency) * 2000. For example, DDR5-6000 CL30 has a lower true latency than DDR5-5200 CL40, even though the frequency is lower.

Conclusion

When buying RAM, look for the best balance. Aim for high frequency paired with the lowest possible CL timing that fits your budget, ensuring you check compatibility with your motherboard's QVL list.