[SOLVED] In regards to CPU memory support for DDR5

[Calicifer]

Greetings,

I'm little bit puzzled about newest generation RAM support. I know that people can get it to advertised speeds with XMP. What I do not understand is how such speeds are supported by CPU. The best available CPU, i9-12900Ks at the moment supports up to DDR5 4800 MT/s. However, you can easily find DDR5 RAM with speeds up to 6400 MT/s. How I'm supposed to use this RAM if existing technology does not support it? Obviously there is more to it and I would like to know why specified CPU RAM support is seemingly detached from reality.

 

[rgd1101]

there OC

 

[Calicifer]

It might be that current processors are still too slow to handle such fast memory. In a same way, newest memory is same or worse than previous generation. Its higher frequencies are made pointless by abysmal latency. Newest tech still seems to be far from comfortably supporting these technologies and there is little point jumping to the bleeding edge. Pointless from performance gains and painful for your wallet.

This is the conclusion I came to when I was thinking about upgrading to modern hardware. It seems that DDR5 won't be ready for about two years at the capabilities I expect from them and even the best processors do not meet criteria I would like to have in my system. At the moment, my build would be pointlessly expensive, especially due to RAM.

 

[Eximo]

That is true of any Intel or AMD generation of CPU you look at. There is the officially supported speed and then the XMP and DOCP are profiles for overclocking.

From what I have seen, 6400 is optimistic with Alder lake, can certainly run into issues when using more then two memory sticks. And buying two kits at the same time is no guarantee of 4 stick compatibility at XMP speeds.

For instance, officially the i9-10900F (a non overclocking chip) supports 2933, I am running 3600 (using a 3200 kit no less) Just takes the right motherboard and a little luck.

Your 5200 and 5600 kits aren't going to be too much a problem to get working. But above that you might have to do some tweaking.

When Raptor Lake shows up, you can expect a bump to the next logical frequency range to be officially supported.

 

[Calicifer]

I'm in no hurry to upgrade. I want 6400 Mhz DDR 5 RAM in Quad channel or at least four slots with 64 GB capacity.

I think that my desires are still on a bleeding edge and I will pay an arm and a leg to get it and will have a lot of problems with such fast RAM. I'm not sure if Raptor Lake will work out all the issues. I might jump to flagship model when intel releases Meteor architecture and meanwhile I will just upgrade my 4'th gen i5 to i7.

 

[Endre]

Greetings,

I'm little bit puzzled about newest generation RAM support. I know that people can get it to advertised speeds with XMP. What I do not understand is how such speeds are supported by CPU. The best available CPU, i9-12900Ks at the moment supports up to DDR5 4800 MT/s. However, you can easily find DDR5 RAM with speeds up to 6400 MT/s. How I'm supposed to use this RAM if existing technology does not support it? Obviously there is more to it and I would like to know why specified CPU RAM support is seemingly detached from reality.

Hello!

We are in the "XMP era" which means that vendors will advertize crazy memory speeds that aren't yet supported natively by any CPU manufacturer.

XMP is, simply, an overclock of the memory controller.
Any voltage increase from 1.1V (on DDR5) or 1.2V (on DDR4) is on your own risk!
Will it work?
Generally, yes, but still, there are plenty of people out there complaining about system instability due to memory OC.

Me, personally, for stability reasons, I stick with the highest speed RAM modules that run at JEDEC approved voltages.

I hope this helps...