We are going to test Corsair Dominator Platinum memory kits in an LGA 2011 system built on Asus P8Z77-V Deluxe mainboard based on the newest Intel Z77 Express chipset. Since overclocking memory modules are primarily purchased by enthusiasts, we also used Intel Core i5-3570K processor overclocked to 4.5 GHz.
As a result, the complete list of hardware and software components in our testbed looked as follows:
- CPU: Core i5-3570X, overclocked to 4.5 GHz (Ivy Bridge, 4 cores, 6 MB L3);
- CPU cooler: NZXT Havik 140;
- Mainboard: ASUS P8Z77-V Deluxe (LGA 1155, Intel Z77 Express);
- Corsair Dominator Platinum CMD8GX3M2A1600C9 (2 x 4 GB, DDR3-1600, 9-9-9-28);
- Corsair Dominator Platinum CMD8GX3M2A1866C9 (2 x 4 GB, DDR3-1866, 9-10-9-27);
- Corsair Dominator Platinum CMD8GX3M2A2133C9 (2 x 4 GB, DDR3-2133, 9-11-10-27);
- Corsair Dominator Platinum CMD16GX3M2A2400C10 (2 x 8 GB, DDR3-2400, 10-12-12-31);
- Corsair Dominator Platinum CMD8GX3M2A2666C11 (2 x 4 GB, DDR3-2666, 11-13-13-35).
- Graphics card: Nvidia GeForce GTX 680 (2 GB / 256 bit GDDR5, 1006/6008 MHz);
- Drive: Intel SSD 520 240 GB (SSDSC2CW240A3K5);
- Power supply unit: Corsair AX1200i (80 Plus Platinum, 1200 W);
- Operating system: Microsoft Windows 7 SP1 Ultimate x64;
- Intel Chipset Driver 126.96.36.1995;
- Intel Management Engine Driver 188.8.131.528;
- Intel Rapid Storage Technology 184.108.40.2060;
- NVIDIA GeForce 306.97 Driver.
As we showed in our special review of the memory controller in modern LGA1155 CPUs, it is the operating frequency of dual-channel memory kits that has the biggest effect on the platform's performance. Therefore, increasing it above standard levels is the key feature of overclocker-friendly memory kits that helps ensure an additional performance boost.
Corsair’s Dominator Platinum series looks promising in this respect as they feature high-quality chips and efficient cooling. In fact, Corsair is known to endow its products with a large safety margin, so we can expect the Dominator Platinum series to be able to work at higher frequencies than their rated ones.
Here’s our algorithm of testing the overclocking potential of DDR3 SDRAM:
- Memory voltage is increased to 1.65 volts which, according to Intel, is the maximum value that doesn’t lead to degradation in the memory controller’s performance. We also increase the VCCSA voltage to 1.0 volts, which should theoretically have a positive effect on the memory controller’s stability;
- Failsafe timings of 11-13-13-31-2N are selected to find out the highest frequency the memory kit is stable at;
- Using the maximum frequency we’ve found, we then look for the most aggressive timings at which the memory kit is still stable.
The stability of the memory subsystem is verified by 10 runs of LinX 0.6.4 AVX Edition using the whole memory amount and by an additional 1-hour-long check with Memtest86+ v4.20.
Corsair Dominator Platinum PC3-12800 C9 2x4 GB (CMD8GX3M2A1600C9)
Rated for DDR3-1600, the simplest Dominator Platinum product in this review turns out to have no overclocking potential. It cannot be stable even at 1800 MHz. The best we could do with our CMD8GX3M2A1600C9 was improve its timings from 9-9-9-24-2T to 9-8-7-24-1T. The clock rate could not be increased.
Thus, the DDR3-1600 Dominator Platinum kit is not really meant for overclockers. It can only be interesting for its modding and monitoring capabilities. If you want higher performance, you should look for more expensive and faster memory kits.
Corsair Dominator Platinum PC3-15000 C9 2x4 GB (CMD8GX3M2A1866C9)
The DDR3-1866 Dominator Platinum kit is not as dull as its DDR3-1600 cousin. It could be overclocked to DDR3-2000 but, unfortunately, not to DDR3-2133 mode.
Moreover, overclocking the CMD8GX3M2A1866C9 kit to 2000 MHz called for a considerable reduction in timings. In its default mode this memory has aggressive timings with a CAS Latency of 9, but in DDR3-2000 mode it is only stable with timings of 11-11-10-31-1T and voltage increased to 1.65 volts. It looks like the manufacturer carefully selects chips for its Dominator Platinum series not only to make sure they are absolutely stable in the specified operation mode. The chips seem to be sorted out in such a way that the best components are used in the most expensive products only.