Practical Memory Settings

[Bloax]

So we have a thing like this, looks great and all - dual-rank 8 gbit Sammy B running at a chilly 1.63v
Bit of a pain to set up, requires a fan, questionable long-term (12+ hour high-intensity workload) stability.

Thus I raise a question to the folks that peruse the place:
How much performance do you expect to see me drop, if I was to lower these values to something much more reasonable?

2x16 GB 3200 CL14-14-14 kits weren't particularly expensive, back when I last looked, and they're more than capable of doing "easy" 3800 16-16-16 at 1.46v with less pushed subtimings.

what's it gonna be??


I'll go run some Tests(tm) after some votes pour in, even if I already have a vague idea of what it's going to be.

 

[Space_Ranger]

I can't speak for the 5000 series of CPUs, but for the 3000 series running RAM at more than 3600 didn't yield any significant performance differences. This was my take-way from:

Ryzen 3000 Memory Benchmark & Best RAM for Ryzen (fClock, uClock, & mClock)

Memory speed on Ryzen has always been a hot subject, with AMD’s 1000 and 2000 series CPUs responding favorably to fast memory while at the same time having difficulty getting past 3200MHz in Gen1. The new Ryzen 3000 chips officially support memory speeds up to 3200MHz and can reliably run kits...

www.gamersnexus.net

 

[Ready4Droid]

Well, you gave no specifics on what you plan to drop to or what work loads you're talking about, so really this could be anything. Just posting to so I don't forget to check back on results .

 

[Dan_D]

I haven't tested the 5000 series, but the 3000 series didn't benefit from memory speeds over 3733MHz according to AMD's own documentation. Some boards you could push it a bit higher if you could get the Infinity Fabric to behave. But clocking over 3800MHz always required a divider, which tanked performance and wasn't worth while. Your FCLK is higher, and you are over 3800MHz, but I can't speak to how the Ryzen 5000 series will handle that. But, that RAM voltage is probably not sustainable. Benchmark it at reasonable settings and see what it does.

 

[Zarathustra]

I usually don't mess with RAM too much. I buy RAM with official specs for the highest non-OC clock the platform I am using supports (or at least only a mild overclock considered practically guaranteed), with the lowest available CL timings, and then just use XMP settings.

In my current case this has been a mild OC of DDR4-3600, and CL16. It seems to work well.

Hasn't failed me yet. It just doesn't seem like it makes enough of a performance difference to worry about doing anything beyond this.

 

[Dan_D]

I've run DDR4 4000MHz+ RAM on the test bench and 3866MHz, etc. on multiple platforms since DDR4 came out. It rarely makes much of a difference.