Before we start discussing the benchmarks results I would like to draw your attention to the voltage on the 1GB memory modules. The thing is that all 1GB memory modules are built using high-density chips and so they do not really tolerate high voltages well by nature. Do not try setting the voltage over 3.0V, because the memory chips may degrade very rapidly. Also, 1GB memory modules overclock pretty well at 2.8V, which is considered to be pretty modest voltage rate from the overclockers’ standpoint. Further voltage increase may negatively affect overclocking results or have no effect at all. Therefore, we didn’t perform all the tests at 3.0V Vmem setting: in this case we experienced 2-10MHz frequency drop and saw no improvement of the overclocking potential whatsoever. That is why we didn’t include the results into any of the score charts below.
Also, our results may not necessarily coincide with your numbers, because there are multiple factors that affect the performance scores: mainboard type, CPU, BIOS settings, “lucky” or “unlucky” memory modules set. But despite this fact, our diagrams will most closely represent the statistics for solutions identical to G.SKILL modules reviewed today.
As usual we will start with the extreme series - F1-4000USU2-2GBHZ. Here is what the SPD reported:
And here are our test results:
The situation is actually quite familiar, looks we have already seen something like that somewhere… Of course, these results have been obtained from the previously tested high-quality memory modules from other manufacturer built on Samsung TCCD chips!
The results were simply impressive: I didn’t expect the reach these frequencies on 1GB memory modules. Way to go, G.SKILL! BY the way, the mainboard we used for our test session works perfectly well with 1T/2T Command Rate setting that is why most likely we couldn’t go beyond 270MHz because of the memory or the CPU memory controller. Or because of them both.
Now let’s analyze the results we have just seen on the diagrams. The picture is the following: until we hit 240MHz, neither voltage nor Command Rate influences the frequency. And the increase is non-linear in this case. The sacred 2-2-2-5 timings can be achieved at shockingly low 165MHz (there are different memory modules designed to work efficiently with these timings, however, they cannot boast 1GB capacity). However once we increase the CAS latency from 2 to 2.5, we immediately gain extra 40MHz putting the memory modules at a very acceptable performance level.
Nevertheless, the results are not that high, which gives us the right to conclude that there are no memory modules of that capacity with universal characteristics. At least, G.SKILL doesn’t have them. The memory modules they offer right now either work at low memory timings (see below for details), or reach high clock speeds. In fact, we see the same situation as 3 years ago when the first DDR500+ memory modules came out.
That is why we are not really interested in the performance of our memory modules at the frequency below 250MHz. and after that the situation gets really interesting. In the hardest conditions (with the nominal memory timings of 3-4-4-8, 1T, 2.66V) the maximum frequency we managed to achieve is 265MHz. It is an excellent result keeping in mind that these are 1GB modules. By setting the Command Rate at 2T we can achieve additional 30MHz gain. And when we change the timings even more until they reach mockingly slow 3-5-5-10 and set the Vmem to 2.8V the outcome is practically null: altogether these changes hardly get us a 10MHz increase.