The second part of our test session is more interesting and informative from a practical standpoint. Here we checked out the memory modules overclocking potential and they proved to have quite a substantial one, I should say. To confirm the system stability we used two utilities that check the proper operation of the memory subsystem under heavy load: Memtest 2.11 and Prime95 25.7 x64.
First of all we decided to find the most aggressive timings with which our memory kits could still work as DDR3-1600. All stability tests were performed at the maximum memory voltage setting recommended by Intel – 1.64 V (most mainboards do not allow setting precisely 1.65 V).
First of all I would like to draw your attention to a phenomenal result demonstrated by Patriot kit. Although this memory is formally designed to work with CAS Latency = 8, it proved capable of working stably at 1600 MHz frequency with CAS Latency lowered to 6. Of course, it is an excellent result and it could be sufficient to recommend DDR3-1600 SDRAM kit from Patriot as the best overclocker choice, but we suspect that we may have received not a mass production kit but specially prepared samples. Unfortunately, at this time we do not have any comments from Patriot on the matter, but we will surely update our data as soon as we do.
Other than that, everything looks pretty logical. Memory with lower default timings can work in more aggressive non-nominal modes. Therefore, it is not surprising that after Patriot, the leadership goes to triple-channel memory kits from Geil, Mushkin and OCZ. We were also very pleased with Kingston’s results, as it allowed us to lower the memory timings to 7-8-7-22, although it is initially intended to work with 8-8-8-24 timings.
Now let’s take a look at the maximum frequency that we manage to achieve with our 6 GB DDR3-1600 SDRAM kits for LGA1366 platforms. The first test in this part of our session was performed with 7-7-7-20 timings and 1.64 V voltage. I have to stress that it is a pretty difficult operational mode for most memory, because the majority of the participating modules are not optimized at all for work with such aggressive timings.
If we leave the exceptional result demonstrated by patriot memory kit aside, the picture is overall quite logical. Those memory modules that were initially declared to work with CAS Latency = 7 overclock beyond 1600 MHz. So, Geil, Mushkin and OCZ demonstrate the best results again, just like in all the previous tests. As for slightly less expensive memory kits with 8-8-8-24 default timings, it is fairly hard to find indisputable leaders here. However, solutions from Crucial, Wintec and Kingston look a little more appealing than their competitors.
The second overclocking test was supposed to reveal the maximum frequencies at which our triple-channel memory kits made of 2 GB DDR3-1600 modules will work stably with less aggressive 8-8-8-24 timings.
As you can easily see, with less aggressive timings the maximum stable frequencies increase dramatically. Some DDR3-1600 SDRAM kits, such as OCZ Reaper and Patriot manage to get as far as to the next frequency threshold – 1867 MHz. Overall, all the memory kits that we have already pointed out above overclocks pretty well even with less aggressive timings. Only Geil kit performed a little worse than usual, and Corsair Dominator memory, on the contrary, got into the leading group.