Corsair Vengeance Pro Review: 2x8 GB at DDR3-2400 10-12-12 1.65 Vby Ian Cutress on December 13, 2013 2:00 PM EST
When it comes to memory overclocking, there are several ways to approach the issue. Typically memory overclocking is rarely required - only those attempting to run benchmarks need worry about pushing the memory to its uppermost limits. It also depends highly on the memory kits being used - memory is similar to processors in the fact that the ICs are binned to a rated speed. The higher the bin, the better the speed - however if there is a demand for lower speed memory, then the higher bin parts may be declocked to increase supply of the lower clocked component. Similarly, for the high end frequency kits, less than 1% of all ICs tested may actually hit the speed of the kit, hence the price for these kits increase exponentially.
With this in mind, there are several ways a user can approach overclocking memory. The art of overclocking memory can be as complex or as simple as the user would like - typically the dark side of memory overclocking requires deep in-depth knowledge of how memory works at a fundamental level. For the purposes of this review, we are taking overclocking in three different scenarios:
a) From XMP, adjust Command Rate from 2T to 1T
b) From XMP, increase Memory Speed strap (e.g. 1333 MHz -> 1400 -> 1600)
c) From XMP, test a range of sub-timings (e.g. 10-12-12 to 13-15-15 to 8-10-10) and find the best MHz theses are rated.
There is plenty of scope to overclock beyond this, such as adjusting voltages or the voltage of the memory controller – for the purposes of this test we raise the memory voltage to the ‘next stage’ above its rated voltage (1.35V to 1.5V, 1.5V to 1.65V, 1.65V to 1.72V). As long as a user is confident with adjusting these settings, then there is a good chance that the results here will be surpassed. There is also the fact that individual sticks of memory may perform better than the rest of the kit, or that one of the modules could be a complete dud and hold the rest of the kit back. For the purpose of this review we are seeing if the memory out of the box, and the performance of the kit as a whole, will work faster at the rated voltage.
In order to ensure that the kit is stable at the new speed, we run the Linpack test within OCCT for five minutes as well as the PovRay benchmark. This is a small but thorough test, and we understand that users may wish to stability test for longer to reassure themselves of a longer element of stability. However for the purposes of throughput, a five minute test will catch immediate errors from the overclocking of the memory.
With this in mind, the kit performed as follows:
|XMP, 2T to 1T||1611.44||79C|
|2600 10-12-12||No Post||No Post|
|Subtimings||Peak MHz||PovRay||OCCT||Final PI|
I was a bit surprised that the memory kit would not add a memory strap to 2600 MHz with the same XMP timings. This was confirmed in our secondary testing over sub-timings: 2400 C9 is the peak of our kit, giving a PI of 267.