Conclusion
According to our tests, today’s Haswell-based platforms perform quite differently with different memory modules. We can’t say anymore that memory subsystem parameters don’t matter. By changing your DDR3 SDRAM parameters, you can actually ensure a performance boost of 20-30%!
Of course, not all applications are that memory-sensitive.
Judging by our test results, you may want to choose high-speed DDR3 SDRAM in two cases: when you build a gaming computer or a home PC for image and HD video processing.
Frequency is more important than timings when it comes to top-end LGA1150 configurations. DDR3 SDRAM kits currently available don't differ much in their timings but vary greatly in terms of their specified clock rate. And indeed, it is the clock rate of DDR3 SDRAM that affects performance the most.
Today’s Haswell-based computers are optimized for high-speed DDR3 SDRAM. You will have no problems setting a memory frequency up to 2933 MHz. We'd recommend choosing the fastest kits available, yet they are too expensive, so we guess DDR3-2400 SDRAM is the most optimal choice right now in terms of price/performance ratio. It ensures much higher performance in comparison with DDR3-1600 while not being much more expensive. Moreover, our tests suggest that the higher memory clock rates have a smaller effect on performance although memory kits faster than 2400 MHz come at much higher prices
