Pushing Your DDR2 RAM To The Max

Corsair XMS2, CM2X512A-5400UL

Corsair only warrants its memory modules for clock speeds up to 675 MHz. We were also able to run them at DDR2-1066 rates as well, but not with complete reliability. In sharp contrast to AData, Corsair pushes the limits on its timing settings : CL3-2-2-8 for DDR2-667 is the tightest we’ve seen, and our benchmarks demonstrate that such values often produce better results than increasing clock rates. For reasons of compatibility, the SPD-ROM values are programmed at CL4-4-4-12, which will work reliably in all motherboards when installed. If you want faster timing settings, you must enter them into the CMOS yourself.

These Corsair Ultra-Latency DIMMs will also work at DDR2-800 clock rates. Although the vendor recommended 2.1V for DDR2-667, which worked nicely at CL3-2-2-8, we had to boost input voltage to 2.2V for DDR2-800. At 2.3V we attained 533 MHz (DDR2-1066) clock rates, but the level of stability we attained didn’t improve with higher voltages. We must emphasize that at clock rates of 333 MHz (DDR2-667) these DIMMs compared favorably to higher clock rates for the other product.

We selected these Corsair DIMMs for this project primarily because of their attractive timing settings. Those benchmark results are marked with the vendor’s name ; all other values apply only to the AData DIMMs.

Impressive numbers : Corsair’s Minimal timings