Let us continue with the most important part of the test report, the highest possible stable performance. The test results are based on an ASRock X99 Extreme6 LGA2011-3 motherboard with an Intel Core i7-5930K CPU on different frequencies depending on the BCLK and RAM clock for the different memory benchmarks. Microsoft Windows 7 Ultimate Edition is used as the operating system. The stability was examined with the software Memtest86
and SiSoft Sandra Lite is used for all benchmarks, because it offers extensive adjustments and a fast result comparison. BTW. the latest SiSoftware Sandra version is available on our server and can be downloaded very fast. The memory benchmark tests are also included in the free Sandra Lite version.
DDR4 benchmark with SPD settings …
First, the memory modules are tested with the SPD values at default BCLK, whereby the values are programmed to the SPD and/or XMP EEPROM IC by the manufacturer and read out from the motherboard. At default BLCK, the timings with the autosettings were set to 16-16-16-39 2T (CAS-TRCD-TRP-TRAS).
Here is a Snipping screenshot of CPU-Z 1.70 at 1199.40 MHz / DDR4-2400 and 16-16-16-39 2T with 1.20 Volt:
Here is the result of the SiSoftware Sandra benchmark tests:
| Default Frequency | Timing | Memory Voltage | RAM Bandwidth Integer B/F AVX2/256 | Memory Bus Range | Memory Latency |
| 1199.4 MHz | SPD 16-16-16-39 | 1.20 Volt | 17.78 GB/s | 19.19 GB/s | 27.3 ns |
By the way, the “Memory Bus Range” is no benchmark value, but this value is quite simple to calculate by the frequency and this is useful for a comparison.
This standard SPD clocking at the standard DDR4 voltage is compared with two other settings:
DDR4 OC with 1.20 Volt …
First, the maximum frequency of the memory modules is determined with default 1.20 Volt. The memory clock with a fixed memory timing of 15-15-15-36 2 T and 1.20V voltage is increased in small steps while the detailed Memtest86 test still runs without errors. The long trial period ensures that this frequency of the modules is working really stable.
The highest frequency with 15-15-15-36 2T timings and 1,20V was approx. 1332.6 MHz.
Here is a Snipping screenshot of CPU-Z 1.70 at 1332.60 MHz / DDR4-2666 and 15-15-15-36 2T with 1.20 Volt:
DDR4 OC with 1.35 Volt …
On the other hand the highest possible frequency was determined at 15-15-15-36 2T with the maximum permitted manufacturer voltage, which is however for these modules identical with the default voltage of 1.20 volts. Since overclocking is already outside the specifications, we decided for an OC voltage of 1.35 volts, to overclock the memory at least slightly higher.
With an increased memory voltage of 1.35 volts the DDR4 memory modules at 15-15-15-36 2T timings could be overclocked to 1400.60 MHz, which corresponds to approximately DDR4-2800. Officially the company Crucial specifies the default DDR4 1.20 volts, without loosing the warranty !
Here is a Snipping screenshot of CPU-Z 1.70 at 1400.60 MHz / DDR4-2800 and 15-15-15-36 2T with 1,35 Volt:
It is possible to run higher frequencies with increased voltages or lower timings, because the frequencies and timings depends directly from each other.
Here, the OC values are shown in a chart:
Thus, the OC results were below the overclocking results of the previously tested ADATA Premier 4GB DDR4-2133 CL15 modules, that we overclocked with 1.20 volts to 1340.70 MHz (DDR4-2684) and with 1.35 volts on 1498.80 MHz (DDR4-3000). Anyway, contrary these Crucial Ballistix Sport 4GB modules offers already 1199.40 MHz (DDR4-2400 CL16) without additional overclocking. A direct comparison of the OC results with other DDR4 modules follows in the next DDR4 test reports.