TechSpot published DDR4 Memory at 4000 MHz, Does It Make a Difference?
A quote from the article:
For the most part we test using DDR4-3000, as it occasionally shows some benefits over the more typical 2400 and 2666 MHz speeds. Going to 4000 MHz and beyond is a massive increase in frequency (and cost) and I struggled to imagine where this would be useful, particularly when gaming. Then again, curiosity had gotten the better of me...DDR4 Memory at 4000 MHz, Does It Make a Difference? @ Techspot