What is the Fastest DDR3 RAM?

The quest for the fastest DDR3 RAM has long been a fascination for both casual users and overclocking enthusiasts. Typically, the fastest DDR3 RAM available operates at speeds of 2400 MT/s or higher. However, this speed can vary significantly based on the manufacturer, the specific model, and the system's compatibility.

Common Speed Ranges

For the general public, DDR3 RAMs come in a variety of frequencies ranging from 800MHz to 1866MHz. These include:

800MHz - The lowest speed, often found in older systems.

1066MHz 1333MHz 1600MHz 1866MHz - The highest speed, typically reserved for enthusiast-level systems and often comes with a heatsink to manage the increased load.

While 1066MHz, 1333MHz, and 1600MHz are the most commonly found in modern systems, the 1866MHz RAM is designed for more advanced builds with top-tier components. By overclocking, you can often push the RAM to 2133MHz, although this is more achievable with 1600MHz and 1866MHz RAM due to the inclusion of a heatsink in the latter.

Understanding Clock Speeds

When discussing RAM speeds, it's essential to understand that the clock speed of DDR3 can vary from 800MHz to 2133MHz. Sometimes, the advertised speed might differ from what the BIOS reports due to system constraints. For example, my old computer had RAM running at 2400MHz, but the BIOS showed 2333MHz. This discrepancy can occur due to limitations in the motherboard or CPU's memory controller.

Factors Affecting Maximum Speed

Making the RAM module run at its peak speed isn't just about the RAM itself; it also depends on the CPU's integrated memory controller. To achieve these higher speeds, the motherboard must support the RAM, and the CPU's controller must be able to handle it without crashing. This is where XMP (Extreme Memory Profile) comes into play. XMP certified kits, such as the PC3-19200, are designed to be stable and perform up to their maximum speeds with the help of optimal voltage settings.

For example, my PC3-19200 XMP certified kit required a couple of years to find the right voltage settings, including the ring voltage, which was crucial for the stability of the memory controller.

Conclusion

The fastest DDR3 RAM, in terms of advertised speed, can reach up to 2133MHz. However, individual results may vary due to system compatibility and manufacturer specifics. If you're looking to push your system to the limits, ensure that your motherboard and CPU can support these speeds, and consider using XMP certified kits for better stability and performance.