Picking RAM to pair with a Ryzen 9 3900x... Help?! lol

[ZeroHostile]

I have read up on the RAM performance when paired with a 3900x and from what I've gathered anything running over 3733 will no longer be utilized at 1:1 and will end up nerfed by the CPU.  It has been a long time since I built a PC (I'm from the era of blue screened BIOS interfaces and manual jumper overclocking lol) and all of this might as well be Greek to me. That said, I have thus far sorted through some reviews and forums and think I have decided on a ASRock X570 Velocita, with a Ryzen 9 3900x.  The MOBO supports higher than 3733 RAM speeds, so I originally looked into RipJaws ddr4-4000, then read up on the CPU compatibility and read some performance reviews where there is some conflicting information.  Some say that 3200 is the "sweet spot" for performance, while others claim the 3600 range offers even better yet.  I tend to lean towards the 3600 "theory" based solely on the fact that, well it's faster lol.  If the 3600 range IS where I'm heading, these are the options I have found Crucial Ballistix 64 GB (2 x 32 GB) DDR4-3600 CL16 Memory and G. Skill Ripjaws V 64 GB (2 x 32 GB) DDR4-3600 CL18 Memory.  Obviously the Ballistix have a lower latency, but is it 65$ worth of increased performance?  Also, if I am mistaken and 3600 is NOT the sweet spot, can someone clarify what I should be looking for to get the most bang for the buck, I don't want a "budget build" but I don't want to pay extra for bells and whistles that I don't need either. Thanks in advance for any assistance. 

 

[YoungBlade]

What are you doing with the computer?

 

In gaming, RAM timings/speeds usually only matter when CPU bound, which is rare, so you probably won't notice a difference. Generally, very few applications are memory bound, but since you're looking at a 12-core CPU, I'm guessing you do have some productivity workloads in mind, and there are some that can benefit from better quality RAM.

[RONOTHAN##]

For clarification, the sweet spot for RAM speed depends on what generation of Zen you're looking at. For Zen and Zen+, 3200MHz is the sweet spot. For Zen 2 and Zen3, 3600MHz is the sweet spot. Either kit you want to buy would be great for your use case, but the difference in timings will only increase or decrease performance by 3-4% at most (depending on workload). Hardware Canucks did a video on it a few months ago if you want to see performance numbers for each memory speed. The choice mainly comes down to how much you're spending on the rest of the system. If you're spending $4000, an extra $65 is basically nothing would be well worth it for the extra 3-4%. If you're spending $1500, then the extra $65 would be and extra 5% of the budget, and not really worth the extra 3-4% performance increase.

[Moonzy]

10 minutes ago, ZeroHostile said:

from what I've gathered anything running over 3733 will no longer be utilized at 1:1 and will end up nerfed by the CPU.

depends on your CPU's fCLK capabilities

if it can run that high then sure (that high = half of RAM's sticker speed)

 

mine can run 1833 no problem (which is 3666 RAM)

while 3600 can be ran on MOST zen 2 chips, not all of them can

if you want safest bet, 3200 CL14 would be great

 

i personally was running 3600 CL18, recently changed to 2666 CL16 because i need more capacity and didn't think the extra speed is worth double the cost for RAM

[ZeroHostile]

1 minute ago, YoungBlade said:

What are you doing with the computer?

 

In gaming, RAM timings/speeds usually only matter when CPU bound, which is rare, so you probably won't notice a difference. Generally, very few applications are memory bound, but since you're looking at a 12-core CPU, I'm guessing you do have some productivity workloads in mind, and there are some that can benefit from better quality RAM.

Honestly, not going to do nearly as much as it's capable of lol... A bit of video editing, and a bit of gaming, but nothing TOO intensive, and yes I know the entire setup I described is freaking overkill, but I figure it should save me having to upgrade for a while, just want to know what plays the nicest with the 3900x in all situations, well rounded if you will.  Currently running a Hp z620 Workstation with 32g ddr3-1600, 12 core Xeon processor, and a RTX 3070 and frankly it does more than what I ask of it, but I have recently found that half my DIMM slots have failed only the 4 to the right of the CPU work or even read RAM, so it is time to upgrade.  BUt again, I will likely NEVER push this thing to half it's potential, just want the option to be there if I do

 

[ZeroHostile]

3 minutes ago, RONOTHAN## said:

For clarification, the sweet spot for RAM speed depends on what generation of Zen you're looking at. For Zen and Zen+, 3200MHz is the sweet spot. For Zen 2 and Zen3, 3600MHz is the sweet spot. Either kit you want to buy would be great for your use case, but the difference in timings will only increase or decrease performance by 3-4% at most (depending on workload). Hardware Canucks did a video on it a few months ago if you want to see performance numbers for each memory speed. The choice mainly comes down to how much you're spending on the rest of the system. If you're spending $4000, an extra $65 is basically nothing would be well worth it for the extra 3-4%. If you're spending $1500, then the extra $65 would be and extra 5% of the budget, and not really worth the extra 3-4% performance increase.

Thanks for the info, I already have a PSU, case, and RTX card, so the RAM/MOBO/CPU and a m.2 drive, is looking to be around 1100, factor the parts I'm reusing its about a 2200$ setup +/- a few bucks... Like I said, I don't want a budget build, but I want outstanding stability I guess is what I should have stated before, so 65$ for peace of mind isn't a bad investment to me

[Hairless Monkey Boy]

First, what do you intend to use this PC for, and for what reason did you land on the 3900X? If the answer is that you intend to use this machine for a majority of productivity work, and you want to save a buck, then it makes sense as a choice, but otherwise a 5800X (if you do more gaming) or 5900X (if you want the best performance for both) might be better options.

 

But to answer your question, 3600Mhz is where you want to be for gaming. With 64GB, it might be prudent to go with 3200Mhz for better compatibility. There is a risk that 3600Mhz at 64GB+ won't work out of the box, and you'll have to tweak settings or end up lowering it to 3200Mhz after all. This advice goes for any of the mentioned CPUs (5800X, 3900X, 5900X) since they share the same memory controller.

[YoungBlade]

1 minute ago, ZeroHostile said:

Honestly, not going to do nearly as much as it's capable of lol... A bit of video editing, and a bit of gaming, but nothing TOO intensive, and yes I know the entire setup I described is freaking overkill, but I figure it should save me having to upgrade for a while, just want to know what plays the nicest with the 3900x in all situations, well rounded if you will.  Currently running a Hp z620 Workstation with 32g ddr3-1600, 12 core Xeon processor, and a RTX 3070 and frankly it does more than what I ask of it, but I have recently found that half my DIMM slots have failed only the 4 to the right of the CPU work or even read RAM, so it is time to upgrade.  BUt again, I will likely NEVER push this thing to half it's potential, just want the option to be there if I do

 

Fair enough. I've got a 5900X, and my justification is that I occasionally do programming and streaming, but it really is overkill for me, too.

 

In that case, the cheaper 3600 kit is fine. You'd never notice a difference unless you ran synthetic benchmarks. If you want to save some money, you could get 2 kits of 2x16GB still totaling 64GB as 2x2x16GB is cheaper right now, but if you want the ability to upgrade to 128GB in the future, then your plan is fine.

[RONOTHAN##]

2 minutes ago, YoungBlade said:

Fair enough. I've got a 5900X, and my justification is that I occasionally do programming and streaming, but it really is overkill for me, too.

 

In that case, the cheaper 3600 kit is fine. You'd never notice a difference unless you ran synthetic benchmarks. If you want to save some money, you could get 2 kits of 2x16GB still totaling 64GB as 2x2x16GB is cheaper right now, but if you want the ability to upgrade to 128GB in the future, then your plan is fine.

Still better than my justification for a 5900X lol. Mine was just "I already spend $2000 on the rest of the system, what's an extra $100 for an extra 4 cores." That and "CPU go brrrrrrrrr"

 

The only thing I have planned to use all the cores is to get GPU-P working on my 3080 so I can run an entire CS:GO team off of one system.