Core i7 Memory Scaling: From DDR3-800 to DDR3-1600


The memory industry, which typically focuses on offering faster (and more expensive) memory products, must find these results rather annoying—there is simply very little benefit to fast DDR3 memory on a fast processor such as the Intel Core i7-975. More than ever, premium RAM can be compared to a high-end sports car: it may provide better performance, but the benefit in everyday life is often very limited.

DDR3 memory kits capable of running beyond DDR3-2000 speeds at increased voltage are the best you can get. However, we limited the testing to DDR3-1600 speed, and stayed at a voltage level of 1.65 V for this article, which represents a reasonable maximum for most users (hitting 2133 in our i7-975 review required a screaming 1.75 V QPI). Our testing included all other selectable RAM speeds, all the way down to DDR3-800, trying both tight and relaxed latencies for each of the RAM clock speed settings.

High End Memory Is Not Worth The Money

The results are obvious: going from one memory speed to the next, e.g. from DDR3-1066 to 1333, does not provide major benefits. Even the replacement of slow DDR3-800 RAM by DDR3-1600 memory will mostly yield disappointing results. While the performance advantage is measurable, it is never noticeable.

Exceptions, however, do exist. Compressing files with WinRAR is significantly quicker on fast, low latency DDR3-1600 RAM. Some applications, such as games, can at least take minor advantage of the upgraded memory horsepower.

What If?

In this light, we decided to add a few more benchmark results at overclocked processor speeds. We decided to accelerate the CPU by one clock speed increment, which reflects exactly what happens if you decide to purchase a faster processor instead of high performance memory.

Click here for all faster CPU benchmarks results.

As you will see, a higher CPU clock speed typically provides better performance in most of the benchmarks—but not in all of them.

Memory Recommendation

Knowing all of these results, it is obvious that highest speed DDR3 memory only makes sense for serious enthusiasts, or for those with unlimited budgets. Everyone else should focus on mainstream clock speeds of DDR3-1066 or DDR3-1333, and go for a trustworthy brand and the quickest timings their budget allows.