DDR (double data rate) SDRAM is the latest evolution in random access memory (RAM) technology. All SDRAM operates on a system frequency or "bus" speed measured in mega hertz (MHz). Traditional SDRAM used only the rising edge of the clock cycle to transfer data. The new DDR SDRAM transferrs data on both the rising and falling edge of the clock. PC2400 is not an actual JEDEC specification but rather a guarantee that the memory will run beyond its specification. PC2400 DDR SDRAM is designed to run stably when overclocked to 150MHz (300MHz DDR). PC2400 describes the memory's transfer rate of 2400 MB/sec (2.4 GB/sec) on a 64-bit bus rather than its MHz speed.

PC2400 DDR uses DDR-266a chips. The DDR-266a chips are the fastest bin rated for CAS2 operation at 266MHz. These modules are programed for CAS 2.5-3-3 operation at 300MHz via the serial presence detect (SPD) EEPROM. PC2400 DDR is designed for use with CPUs which run on a 133MHz FSB (266MHz DDR) but which are known to run stably when overclocked to a 150MHz (300MHz DDR) FSB. Although the increase in bus speed from 266MHz to 300MHz does translate to an increase in performance, a much larger gain comes from using DDR which runs at lower latencies. If the fastest possible performance from your system is important to you, we recommend using our High Performance DDR with the lower latencies over using PC2400 which runs at a faster bus frequency but with higher latencies.

Please consult our DDR mainboard qualification page to see a list of chipsets which have been approved as compatible with our DDR modules.