News DDR4-4000 Rumored To Be The New Sweet Spot For AMD Ryzen 5000 CPUs

Syntextoxy

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I highly doubt it, I think I was watching either Jaystwocents or gamers nexus about the reveal, and the comparisons amd made to Nvidia and Intel, they asked amd about the systems they used and were told they used the same systems and mentioned 3600mhz. And during a reveal they're sure to use all the sweet spots they can to get better results for the reveal. So I think 3600 mhz is still gonna be the same sweet spot as with the 3000 cpus.
 
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DDR4-4000 is to Ryzen 5000 Series as DDR4-3800 was to AMD Ryzen 3000 Series - good luck!
That sounds less like the "sweet spot" and more like the limit. I would argue that the "sweet spot" is the point where going faster doesn't make much sense from a price to performance standpoint.

DDR4-3600 generally doesn't cost much more than 10% or so more than a comparable kit of DDR4-3200. The CPU performance gains it brings typically amount to no more than a few percent at best, but that can be considered worth an extra $5-$10 or so.

For DDR4-4000 though (or really any speed faster than 3600), the price climbs much more, generally being close to twice as much as a comparable kit of DDR4-3600. Even if you are looking to gain maybe a few percent more performance at some tasks, now you're paying substantially more for that mostly imperceptible performance bump. For the vast majority of people, that's not going to be worth the premium.

So, DDR4-3600 will likely continue to be the "sweet spot" for Ryzen 5000, at least unless we see a substantial price drop for the higher speeds at some point.
 

daworstplaya

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Then 4000 for the Ryzen 6000 ;)
Zen4 / Ryzen 6000 will use DDR5.
I can see this being possible now since the Infinity fabric doesn't need to talk between 2 CCXs any more for a 8 Core Zen3 part (Eg: 3800x). Now there is only 1 CCX for an 8 core part, so they could possibly bump up the Infinity fabric speed a little before having to switch to 2:1 mode. DDR 4000 sounds very plausible if they have optimized the layout of the architecture on the chip lowering heat towards the memory controller. DDR4000 with tight timings could be worth a bit. Exciting times.
 

torbjorn.lindgren

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This is old rumour that seems to surface again and again...
The memory controller is exactly the same as with 3000 series, so the ram speed has not been chanced. Aka 3600 is the sweet spot. 3733 if you Are lucky.
Yes, the IO chiplet that contains the memory controllers has not changed but... that's usually NOT the limiting factor on Ryzen.
The limiting factor on this interconnect clock is likely the traces on the interposer going between the cpu chiplet(s) and the IO chiplet.
So it might be possible to clock it higher despite not changing the IO chiplet if AMD use better material in the interposer or it might even just be a case of needing to tweak the trace layout on the interposer to improve signal integrity - this is similar to how newer AM4 motherboards tends to be able to clock the same memory much higher than say B350 motherboards even in cases where they're tested using exactly the same CPU and the BIOS'es uses the exactly same AGESA version (the code from AMD included in the BIOS that sets up a lot of basic parameters including base setup of the memory controller).
This article had no place on Tom's in the first place, this is Wccftech-grade random rumor, Tom's supposed to be better than that!
 

russell_john

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What will happen if the Memory clocks are higher than the CPU clocks? no speed gain I suppose over the CPU clocks right?
The Core Clocks and the IMC clocks are two different things ...... Ryzen works best with DDr4 that is twice the IMC clock ..... For instance it is almost always going to hit 1800 MHZ for Ryzen 3000 so the best memory is 3600 although if you get lucky the IMC clock will hit 1900 MHz and you can clock the RAM at 3800 ..... Very seldom (Maybe 1 in 1000) you can get it to 2000 MHZ and use 4000

However since they didn't make any changes to the IMC in the 5000 series it's likely only going to be able to clock to the same speeds as Ryzen 3000 but we might see more units occasional hit the 1900MHz and 2000 MHz since there have been slight improvement in the TSMC process
 
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Darkbreeze

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If we look on the current market, the Patriot Viper 4 Blackout DDR4 16GB (2x8GB), which retails for $84.99, is the cheapest DDR4-4000 memory kit in the 16GB category. The timings aren't as impressive as the frequency though. The memory kit has its timings configured at 19-21-21-41. However, there are some pretty decent DDR4-4000 offerings on the market, but they carry a heavy premium. For example, the G.Skill Ripjaws V DDR4-4000 16GB (2x8GB) boasts timings of 15-16-16-36, but presently retails for $159.99.
You're kidding right? A heavy premium? You do recall that 16GB of ANY kind of memory, including 2133mhz, was running that price a year ago right? And anything over 3000mhz was much closer to 200 dollars or more? 4000mhz DIMMs with CL15 timings, in a 16GB kit for 160 bucks seems pretty damn decent to me.
 

Makaveli

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Alleged AMD Ryzen 5000 slide shows that the Zen 3 processors will leverage DDR4-4000 memory modules.

DDR4-4000 Rumored To Be The New Sweet Spot For AMD Ryzen 5000 CPUs : Read more
This is information i've been waiting for.

i'm going Zen 3 for sure but need to know which memory is going to be optimal for it. I'm currently on 2x8 3200 CL14 sticks, so do I overclock my current memory to hit those speeds which is doable on these B-die sticks or do I look at DDR4000 sticks.

 
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InvalidError

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i'm going Zen 3 for sure but need to know which memory is going to be optimal for it. I'm currently on 2x8 3200 CL14 sticks, so do I overclock my current memory to hit those speeds which is doable on these B-die sticks or do I look at DDR4000 sticks.
With twice as much L3 accessible to all cores within a CCD and no IF between cores within a CCD, I'd expect fabric clock to be significantly less important on Zen 3 for single CCD CPUs.
 
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Makaveli

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With twice as much L3 accessible to all cores within a CCD and no IF between cores within a CCD, I'd expect fabric clock to be significantly less important on Zen 3 for single CCD CPUs.
I think you are 100% correct. Can't wait for memory testing to be done in the reviews. I may not need to do much with the quality sticks I have. I do intend to go up to 4x8 for 32GB at some point.

This is old rumour that seems to surface again and again...
The memory controller is exactly the same as with 3000 series, so the ram speed has not been chanced. Aka 3600 is the sweet spot. 3733 if you Are lucky.
Agreed to me its

3600 Speed spot

3733 lucky but doable

3800 very lucky not to common
 
If the clocks of the RAM is higher of the clocks of the CPU , there is no way the CPU can handle it and take full advantage of it.
Clock speed is only part of the equation that is how much bandwidth the memory has. You can do something weird like narrow the bus to 16-bit from 64-bit. Now the DDR module has to be clocked 4 times faster to achieve the same bandwidth performance. So if we take a DDR4-3200, which is clocked at 1600MHz, putting it on a 16-bit bus would require it to be clocked at 6400MHz to achieve the same bandwidth.

On a side note, reach Zen core has an internal data bus bandwidth of 32 bytes per clock. This is per core. So even given something like a 6-core Ryzen 5 running at 4.0GHz, you'd need something around 715 GB/sec to completely saturate the processor. And that's assuming the processor is actually processing 32 bytes every clock cycle (it likely isn't)

can any one please explain to me why memory timings are not made the same for all kits ? I assume they cost the same to manufacture ?
Timings are clock cycle count. The faster the clock speed, the tighter the timing becomes and soon enough the RAM misses its window to perform whatever step was needed. Timing numbers that are higher are necessarily bad if we're comparing a faster kit to a slower one.
 

nofanneeded

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Timings are clock cycle count. The faster the clock speed, the tighter the timing becomes and soon enough the RAM misses its window to perform whatever step was needed. Timing numbers that are higher are necessarily bad if we're comparing a faster kit to a slower one.
I know what Timings are , I was asking why are they made in different timings on the silicon level and sold for much higher price while they cost the same to make on the silicon level
 
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"Good on ya, Tom's" for catching and flagging the B.S. in the original 'news' releases on this. The "3800" MHz claim as being AMD's recommendation for existing Ryzen 3000 Zen 2 CPUs was the first I'd seen any such story...and as a 3950X 'prosumer' I track this info pretty tight. Nonetheless, any number of media outlets were reporting it with the Turkish news article as being some sort of fact, even though it was totally unsubstantiated. Thanks again.

As an aside, I run my 3950X with G.Skill Trident Z Neo Series 32GB (2 x 16GB) 288-Pin SDRAM PC4-28800 DDR4 3600MHz CL16-19-19-39 1.35V. If anyone has a better idea, I'm all ears.
 

nofanneeded

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I assume its because of flaws. the lower timings have a flaw

not unlike the AMD Phenom Chips having a bad core, so it was turned off and sold as a dual or triple core instead of 4 core
CAS Latency is how many clock Cycles it takes to deliver data from one of its column after the read command ... I assume that this follows circuit specific design , not like they have higher fail rate at production level ?
 

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