Hacker News Reader

Comment by Dalewyn | Hacker News Reader

>How do you define "non-enthusiast hardware"?

That OEM motherboard in your big box tower.

>All consumer AMD CPUs should be able to clock up to 6000 MT/s and Raptor Lake should do 6600 MT/s stable at the very least with Hynix M-dies. 5600 MT/s is not even an overclock on Intel CPUs.

DDR5 speeds currently crash like a rock if there's more than one DIMM per channel, even moreso if those DIMMs have two ranks rather than one.

I've got four sticks of 16GB DDR5 5600MHz in my Intel i7 12700K, Z690 system. The best I can get the RAM going is 4800MHz, which is still an overclock because Intel's memory controller goes down to 4000MHz rated clock speed with this setup (two DIMMs per channel, 1 rank per DIMM).

View on HN

> DDR5 speeds currently crash like a rock if there's more than one DIMM per channel, even moreso if those DIMMs have two ranks rather than one.

How would you determine that with dmidecode?

Yes, that currently doesn't work well, but most people are using 1DPC, not 2DPC. You can't really even find a kit with 4 DDR5 sticks.

>You can't really even find a kit with 4 DDR5 sticks.

You can: https://www.newegg.com/corsair-64gb/p/N82E16820236933

Maybe once prices come down more I'll consider going to two sticks of 32GB instead of four sticks of 16GB, who knows.

At least in my country (New Zealand) only Newegg (which ships from US and has very expensive shipping) seems to have these 4 stick DDR5 kits and only from Crucial and they are all more expensive than a 2 stick kit with the same capacity, so I'm not sure why anyone would get them.

There weren't any 32GB sticks back when I put my system together, so it is what it is. :V

Populating all of your RAM slots with matched RAM improves your overall bandwidth. A 2x8GB set will run in dual-channel mode, the 4x4 set will run in quad-channel mode (if the CPU supports it, most times it's dual-channel.) The 4x4 set will allow for more bandwidth vs the 2x8. Not quite double, but it reaches at it. Every other metric doesn't really see much of an improvement, though, so this only helps out in bandwidth-intensive applications.

In my (and probably most peoples') case I'm running in dual channel, so that's two 16GB DIMMs per channel. This makes the memory controller clock down to 4000MHz rated.

>You can't really even find a kit with 4 DDR5 sticks.

https://www.corsair.com/ww/en/Categories/Products/Memory/VEN...

4 X 48GB DDR5 5200 40CL latency. G-Skill just came out with some new kits that are even faster.

Reply on news.ycombinator.com