We could say almost the same about the results obtained in applications. DDR3 memory improves the performance differently depending on the type of load; however, it is indisputably better than the old memory standard in all tests.
So, those overclockers who have their systems running at comparatively high bus speeds will be the first to feel the actual effect from DDR3-1600. According to our tests, high-speed memory starts really paying back when the FSB frequency gets far beyond the nominal levels. Moreover, DDR3 SDRAM offers a wide range of dividers setting the FSB-to-memory frequency ratio. It not only gives you more freedom during overclocking, but may become the ultimate success factor for setting new overclocking records.
The obtained test results suggest one more interesting thing: how efficient high bus frequency could be in LGA775 platforms. Just compare the benchmark results obtained at 4.0GHz CPU speed set as 10 x 400MHz and 8 x 500MHz. If you use DDR2-1067 memory with 5-5-5-15 timings, the results turn out pretty unpredictable:
Although it may seem illogical at first glance, the 500MHz FSB doesn’t provide any advantage to the system equipped with DDR2 SDRAM. Moreover, faster bus will, on the contrary, lower the system performance in most cases. In fact, there is a very simple explanation to that. First, by raising the processor bus frequency you increase the internal latency of the chipset North Bridge (Performance Level), and higher performance of the memory subsystem cannot make up for it. Second, when we tested our system at 500MHz FSB, we had to slightly lower the memory frequency, so it actually worked as DDR2-1000. It is important to remember that we didn’t do it in order to ruin the race for DDR2. It is the only possible mode in this case, because Intel’s LGA775 chipsets support very limited range of memory frequency dividers. In case of dramatic FSB frequency increase there is only one divider we could use for DDR2 memory: the “synchronous” one.
The picture turns completely different if we compare the results obtained for DDR3-1600:
All test results indicate a performance increase resulting from the higher bandwidth of the processor bus. However, it is a pretty relative win we are talking about here. It doesn’t exceed 1% on average. Inevitable Performance Level increase during FSB overclocking has its negative effect also with DDR3-1600 SDRAM.
So, the obtained results indicate clearly that FSB overclocking doesn’t have any individual practical value. It only makes sense to set high front side bus frequencies in order to reach high processor clock speeds or to overclock the memory. If you can get the same processor and memory frequency from higher FSB speed as well as from higher multiplier, you shouldn’t focus on the bus frequency increase. However, if your overclocking experience requires setting the FSB at 400-500MHz or even higher, it is important to understand that DDR2 memory will “slow down” the system and you will be able to fully reveal the system potential only with high-speed DDR3.
The results of this investigation also allow making one important conclusion: DDR3-1600 may be demanded. However, you can really benefit from its high speed only if you use high FSB frequencies or 500MHz+. In these operational conditions it does provide better performance than previous generation memory. Therefore, this memory may be of interest only to overclockers, who also value DDR3 for a richer selection of memory frequency dividers and wider opportunities for system performance optimization.
If you have read that far already and are still interested in DDR3-1600 SDRAM, we would like to introduce to you a number of 4GB memory kits for computer enthusiasts available in the today’s market from the leading memory makers.