Performance @ Rated Speeds
Next, we continued testing with SiSoftware's SANDRA, but we manually set the memory timings on the Corsair TWIN2X2048-10000C5DF modules to their rated settings of 5-5-5-18 (CAS Latency = 5T, RAS to CAS Delay (tRCD) = 5T, Row Precharge (tRP) = 5T, Active to Precharge Delay (tRAS) = 18T) at 1250MHz. We achieved these speeds by dropping our CPU's multiplier to 7x and raising the FSB to 1666MHz (416MHz quad-pumped) with the memory and FSB linked via the EVGA nForce 680i SLI motherboard's BIOS. The end result was a CPU clock speed of 2916MHz.
We performed a similar procedure for the Corsair TWIN2X2048-8500C5 and OCZ PC2-8000 Platinum memory kits as well, but there were slight differences in the CPU speed in the end. To hit 1066MHz with the Corsair 8500C5 kit, we dropped the multiplier to 8x and raised the FSB to 1422MHz, which resulted in a 2844MHz CPU clock. And for the OCZ kit, which is rated for 1000MHz at 5-5-5-15, we dropped the multiplier to 9 and raised the FSB to 1333MHz, for a final CPU clock of 2997MHz.
Running the Corsair TWIN2X2048-10000C5DF memory kit at its rated speeds and timings resulted in a huge performance increase. While running at its rated speeds, the kit put up bandwidth scores almost 3GB/s higher than stock DDR2-800. Latency was also decreased from 85ns down to 69ns. The results also show the kind of bandwidth increases and latency reductions offered to users who run their memory at 1250MHz, 1066MHz, and 1000MHz.