We are going to test Kingston 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);
- Kingston HyperX Genesis KHX1600C9D3K2/8G (2 x 4 GB, DDR3-1600, 9-9-9-27);
- Kingston HyperX Genesis KHX1866C9D3K2/8GX (2 x 4 GB, DDR3-1866, 9-11-9-27);
- Kingston HyperX T1 KHX1866C9D3T1K2/8GX (2 x 4 GB, DDR3-1866, 9-11-9-27);
- Kingston HyperX T1 KHX21C11T1K2/8X (2 x 4 GB, DDR3-2133, 11-12-11-30);
- Kingston HyperX T1 KHX24C11T1K2/8X (2 x 4 GB, DDR3-2400, 11-13-11-30).
- Graphics card: Nvidia GeForce GTX 680 (2 GB / 256 bit GDDR5, 1006/6008 MHz);
- Drive: Intel SSD 520 240 GB (SSDSC2CW240A3K5);
- Power supply unit: Chieftec BPS-650C (650 W);
- Operating system: Microsoft Windows 7 SP1 Ultimate x64;
- Intel Chipset Driver 184.108.40.2069;
- Intel Management Engine Driver 220.127.116.119;
- Intel Rapid Storage Technology 18.104.22.1686;
- NVIDIA GeForce 301.42 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.
Kingston’s memory looks promising in this respect. The different HyperX T1 series products use the same chips up to a clock rate of 2400 MHz, and the HyperX Genesis employs chips which are highly regarded by overclockers, too. Kingston’s leading position on the market of enthusiast-targeted memory should also be taken into account. The company is known to ensure a large safety margin for its products, so we can expect that the memory kits we've got today are actually capable of working at much higher clock rates than written in their specs.
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.
Kingston HyperX Genesis KHX1600C9D3K2/8G
The slowest product in this review (rated for DDR3-1600) overclocks rather well. Although based on Micron D9PFJ chips, which are not valued by overclockers much, the KHX1600C9D3K2/8G kit was stable after an impressive 533MHz increase in frequency.
Thus, this memory worked as DDR3-2133, but with not-very-aggressive timings. The 11-12-10-33-1N timings are quite typical of memory modules working at clock rates above 2 GHz, though.
Kingston HyperX Genesis KHX1866C9D3K2/8GX
The fastest product in the HyperX Genesis series was found to have lower overclocking potential. This is quite a surprise since the KHX1866C9D3K2/8GX modules employ overclocker-friendly Hynix H5TQ2G83BFR-H9C chips, but the fact is this kit was unstable if we increased its clock rate by more than 266 MHz.
So, the best result is DDR3-2133 mode with timings of 11-12-11-33-1N.
Kingston HyperX T1 KHX1866C9D3T1K2/8GX
Similar to the KHX1866C9D3K2/8GX in terms of specs, the HyperX T1 KHX1866C9D3T1K2/8GX modules behave absolutely differently in our tests. As opposed to their Genesis counterparts, they can work blamelessly in the fast DDR3-2400 mode.
Well, that’s not surprising, really. All HyperX T1 series modules, including the DDR3-1866, DDR3-2133 and DDR3-2400 ones, are based on identical memory chips. Thus, the ability of the KHX1866C9D3T1K2/8GX kit to work at 2400 MHz with timings of 11-13-12-33-1N is something that can be expected by those users who want to save some money.
Kingston HyperX T1 KHX21C11T1K2/8X
The DDR3-2133 kit from the HyperX T1 series is identical in its components to the other T1 products. That’s why the HyperX T1 KHX21C11T1K2/8X kit did exactly like the HyperX T1 KHX1866C9D3T1K2/8GX in our tests.
The DDR3-2400 mode with timings of 11-13-12-35-1N looks impressive but we shouldn’t forget that this is a mere 266 MHz above the modules’ rated speed.
Kingston HyperX T1 KHX24C11T1K2/8X
This is the flagship HyperX series product and the highest-frequency offer from Kingston currently. Hopefully, this DDR3-2400 kit can amaze us in one way or another…
Unfortunately, like the rest of the HyperX T1 series, the KHX24C11T1K2/8X can only work at 2400 MHz. This frequency was good with the previous kits but only equals the rated clock rate of this one. These modules cannot work at clock rates above 2400 MHz, even as DDR3-2600. Thus, the outcome of our overclocking experiments with the KHX24C11T1K2/8X kit is just laughable as we only managed to reduce one timing (tRP) by one cycle.
Let's sum up our overclocking results in the following table: