Friday, May 10th 2019

AMD Ryzen 3000 "Zen 2" a Memory OC Beast, DDR4-5000 Possible
AMD's 3rd generation Ryzen (3000-series) processors will overcome a vast number of memory limitations faced by older Ryzen chips. With Zen 2, the company decided to separate the memory controller from the CPU cores into a separate chip, called "IO die". Our resident Ryzen memory guru Yuri "1usmus" Bubliy, author of DRAM Calculator for Ryzen, found technical info that confirms just how much progress AMD has been making.
The third generation Ryzen processors will be able to match their Intel counterparts when it comes to memory overclocking. In the Zen 2 BIOS, the memory frequency options go all the way up to "DDR4-5000", which is a huge increase over the first Ryzens. The DRAM clock is still linked to the Infinity Fabric (IF) clock domain, which means at DDR4-5000, Infinity Fabric would tick at 5000 MHz DDR, too. Since that rate is out of reach for IF, AMD has decided to add a new 1/2 divider mode for their on-chip bus. When enabled, it will run Infinity Fabric at half the DRAM actual clock (eg: 1250 MHz for DDR4-5000).This could turn into an additional selling point for AMD X570 chipset motherboards, as they'll have a memory frequency headroom advantage over boards based on older chipsets as their BIOS will include not just the increased memory clock limit, but also the divider mode. Of course this doesn't mean that you can just magically overclock any memory kit to these 5 GHz speeds - it's probable that only the best of the best modules will be able to get close to these speeds.
1usmus also discovered that the platform adds a SoC OC mode and VDDG voltage control. We've heard from several sources that AMD invested heavily in improving memory compatibility, especially in the wake of Samsung discontinuing its B-die DRAM chips.
The third generation Ryzen processors will be able to match their Intel counterparts when it comes to memory overclocking. In the Zen 2 BIOS, the memory frequency options go all the way up to "DDR4-5000", which is a huge increase over the first Ryzens. The DRAM clock is still linked to the Infinity Fabric (IF) clock domain, which means at DDR4-5000, Infinity Fabric would tick at 5000 MHz DDR, too. Since that rate is out of reach for IF, AMD has decided to add a new 1/2 divider mode for their on-chip bus. When enabled, it will run Infinity Fabric at half the DRAM actual clock (eg: 1250 MHz for DDR4-5000).This could turn into an additional selling point for AMD X570 chipset motherboards, as they'll have a memory frequency headroom advantage over boards based on older chipsets as their BIOS will include not just the increased memory clock limit, but also the divider mode. Of course this doesn't mean that you can just magically overclock any memory kit to these 5 GHz speeds - it's probable that only the best of the best modules will be able to get close to these speeds.
1usmus also discovered that the platform adds a SoC OC mode and VDDG voltage control. We've heard from several sources that AMD invested heavily in improving memory compatibility, especially in the wake of Samsung discontinuing its B-die DRAM chips.
112 Comments on AMD Ryzen 3000 "Zen 2" a Memory OC Beast, DDR4-5000 Possible
I am sure AMD is working out a way to allow ZEN to accept faster IF speeds, and hopefully we will see much faster IF interconnect speeds with ZEN3+ Once again, IF is not the issue here from how I read into it, the issue is that the Current ZEN CCXs cannot handle faster IF speeds, if it would, AMD would have added a multiplier where it would run IF at 2x or 3x the IMC. IF isn't the problem here people, but again ZEN is a new design, and I am sure AMD is working it out so it can accept faster IF speeds,
Nevertheless, even with the latency hit due to CCX to CCX communication, ZEN runs amazing and is king of Multi-threading. Newer ZEN designs will only add to this achievement. I am curious to see Benchmarks & Stability Tests done on manipulating this "New 1/2 Divider Mode" if possible to pump up the IF speed and see what happens. :D:nutkick:
And here I am happy with this.
DDR4 5K with Samsung B-die
I mean can you push 1:1:1 ratio higher than 3733mhz ?
With B-die @ 4800C14 and fclk 1900, almost match 9900K with identical memory settings
B-die 5K DOCP with 4800C18 @ XMP
last week Msi released some new bios updates and I grabbed the latest release for my B450m gaming plus, the latest release addressed memory compatibility issues, I've also noticed my post is much faster than before especially when I reboot, it was not just zen 2 compatibility issues on the older chipset but memory too, all sorted now, way to go Msi !