Using Faster Native RAM Speed on 7th, 8th Gen Intel

[Bubbzilla]

I have a couple of PCs with 7th Gen and 8th Gen Intel CPUs. My understanding is that they natively support 2400 MHz and 2666 MHz RAM respectively.

One has an i7-7700 CPU with a MSI Z270-A Pro motherboard and 2x8gb 2400 MHz Corsair Vengeance LPX RAM.

The other has an i3-8100 with a Gigabyte Z370 Aorus WiFi Gaming motherboard and 2x4gb 2666 MHz Corsair Vengeance LPX RAM.

The motherboard specs claim that these ram speeds are supported. But in the BIOS it shows the RAM speed is 2133 MHz. When I try to change clock speeds, the RAM clock is greyed out. I have no experience adjusting PC clock speeds so I don't know what I'm doing. Am I misinterpreting the specifications or am I missing a step?

Thanks in advance for your helpful comments.

 

[SugarJ]

Check to see if you have an XMP option. If you enable XMP it should automatically use the highest stock settings from the ram manufacturer.

 

[Marzipan]

you need to turn on the advanced settings so you can access the overclocking features/functions.

odd how XMP, a feature made to auto-set faster RAM speeds, doesn't always work.

 

[Vittra]

Official JEDEC specifications are that DDR4 is 2133mhz. Motherboards should always initialize ram at the JEDEC spec unless there is manual user intervention to enable an XMP profile - that's intended operation.

XMP profiles are Intel's officially supported way of settings speeds beyond JEDEC which are supported by the CPU and Chipset. Keep in mind that anything beyond Intel's own officially supported speeds is considered an overclock of the IMC (Integrated Memory Controller) of the CPU.

Also keep in mind that some vendors motherboards may additionally enable a CPU clockspeed overclock (and subsequent voltage increase) when you enable XMP - on Asus boards specifically this is called "MCE" or Multicore-enhancement. This was revised during the period of Skylake via BIOS/UEFI updates to warn the user of this and ask if you wish to use stock Intel operation - but only on more recent boards have they made the language more clear about it.

 

[Bond007]

Official JEDEC specifications are that DDR4 is 2133mhz. Motherboards should always initialize ram at the JEDEC spec unless there is manual user intervention to enable an XMP profile - that's intended operation.

XMP profiles are Intel's officially supported way of settings speeds beyond JEDEC which are supported by the CPU and Chipset. Keep in mind that anything beyond Intel's own officially supported speeds is considered an overclock of the IMC (Integrated Memory Controller) of the CPU.

Also keep in mind that some vendors motherboards may additionally enable a CPU clockspeed overclock (and subsequent voltage increase) when you enable XMP - on Asus boards specifically this is called "MCE" or Multicore-enhancement. This was revised during the period of Skylake via BIOS/UEFI updates to warn the user of this and ask if you wish to use stock Intel operation - but only on more recent boards have they made the language more clear about it.

This.

I don’t think it could be said any more clearly.

 

[Bubbzilla]

Thanks for the replies. Very clear and helpful.

 

[Sagath]

the brand new chipset motherboards that support the 8th gen intel cpu's have ram compatibility up to like, 4333MHz in some cases, is this really an issue i should be worried about? Should i try to exchange my ram for the lower speed 2666MHz? Or like intel said, would a motherboard really bottleneck ram to match down to the cpu compatible speeds?

RAM speed does give you a benchmark percentage increase up to a point, but its not that crazy if you're going from 2133 to 3600. Single digit percentages at most. Ryzen is a lot more ram speed intensive.

Just buy the fastest your budget allows.