AMD Ryzen CPU Reviews and Previews (3000 series)

I'm not sure I trust those videos. At least going by the AnandTech review.

The 3700x was unable to go over the power limit set for the chip. The same was true for the 3900x (which shares the same power limit as the 3800x).

Would be nice to see AnandTech test the 3800x, 3600x, and 3600.

Regards,
SB

 

this patent looks to be Zen2's AGU scheduler, its a bit more complex that described on block diagrams

http://www.freepatentsonline.com/20190196839.pdf


edit: from my reading, it looks like the 3rd AGU in effect has a 1 cycle issuing delay, which seems like a smart trade off for relaxing of timings etc needed to schedule 3 operations from the one queue.

edit2: i guess if there is a need they should easily be able to scale to a 4th AGU using the same method.

 

Gigabyte removes PCIe 4.0 support on all AMD motherboards that are not X570
08/05/2019

https://www.guru3d.com/news-story/gigabyte-removes-pcie-4-support-on-all-amd-motherboards-that-are-not-x570.html

 

Was the PCIe 4.0 connection ever shown fully working on X470 motherboards?

I thought the reason why most X570 motherboards need a fan on the chipset is because of PCIe 4.0. Enabling that on a X470 chipset with a small heatsink could lead to heat damage.

 

When it was first discovered ComputerBase did mention a Chinese site tested an Asus motherboard, but not sure subsequent tests. I believe the feature is still available on other motherboard brands.

https://forum.beyond3d.com/posts/2077054/

 

Yes, several different motherboards with X3xx and X4xx chipset paired with 5700 Radeon work in PCIe 4.0 mode. GPU-Z detects Gen4 mode and 3DMark feature test performs at the same level as X570 boards.

 

Mostly because the chipset is an IO die not optimized for this rôle imo.

 

The chipset has absolutely no role with the PCIe4 support on 300- and 400-series, it's only for the CPU connected slots

 

Ok, I thought the 20 lanes from the CPU had to go through the chipset which would work as a multiplexer, but it's like you said:





The reason for X570's higher power consumption is indeed because of PCIe 4.0, but it's from the chipset controlled lanes:

Then there should be no reason for previous chipsets not to support PCIe 4.0 on the graphics cards and the CPU-controlled NVMe interface.

 

The original plan was that any mobo which could meet the pcie4 requirements on slot wiring would support it, but for whatever reason they backed out if it. Apparently some manufacturers still plan to provide the support, but that would mean severe delays in future BIOS-updates as they'd need to circumvent AGESA limiting the support

 

I wonder why.
AMD becoming greedy about forcing sales of X570 motherboards wouldn't exactly fit with their current marketing push for bragging about many generations of forward compatibility on their chipsets.
I guess if there are very few exclusive things about the X570 in comparison to the older X470 (reallistically it's just being able to use PCIe 4.0 on the second NVMe M.2 slot), then there'd be little reason for people to even choose a higher priced X570 instead of a X470 when building a new system in 2019-2020 (let alone upgrading).
Perhaps the OEMs are the ones who got concerned about how little the X570 brought to the table if they let the CPU-driven PCIe lanes work at 4.0 on the older B450/X470 motherboards.

 

X570 sales could be one factor, other could be not wanting to confuse markets with some 300/400 motherboards supporting pcie4 on one x16 and one M.2, others supporting it only on x16, some with just on M.2 and some on neither

 

Surely its mainly the quality of the traces on the mobos?
I think they said X570 mobos have a couple more layers to ensure clean enough signal -> older mobos presumably don't have reliably good enough traces to meet the min-specs for 4.0.

Something I wonder: if the higher chipset TDP is because of 4.0 will they run at lower TDP if operating in 3.0 mode?

 

Using PCIe 4.0 from the CPU doesn't make the chipset run hotter. The issue is that the x570 chipset is fully PCIe 4.0, and runs much hotter than older chipsets. What these motherboards tried to do was enable 4.0 for the PCI lanes that run directly from the CPU, that is, the GPU and the NVMe connectors.

 

The TDP is much higher but de8auer tests couldn't get it to output anything close to the rated amount of power with several drives, including a PCIe 4 NVMe on the chipset running at 5Gb/sec as rated. The theory, though I haven't seen substantiated anywhere, is that running RAID 0 PCIe 4 NVMe on the chipset might cause much higher power usage.

 

OK, FINALLY managed to find a 3700x in stock at Newegg (still no dice at Amazon) and have one on the way. Since, that happened I went to look to see if x370 would be at a serious performance deficit versus x570 and whether people with my MB (Taichi x370) were having problems with these CPUs. The good news is no and no.

https://www.overclock3d.net/reviews/cpu_mainboard/amd_x370_vs_x470_vs_x570_-_3600x_3700x_review/1

In case anyone else is in a situation with having a robust x370 or even x470 MB and is thinking about whether or not to pair it with the new CPUs. There is virtually no performance difference in the vast majority of cases.

So as long as you don't need the new features (PCIE 4.0 being the biggest one), there's not really a need to get a new MB.

In my case, everything up to a 3900x will work in my MB, and people have had success running RAM at 3600+ speeds. However, some people have needed to tweak settings to get it to not run at max power all the time. Hopefully, my adventure will be one of the more trouble free ones.

While I want to jump on PCIE 4.0, I also don't want to have active cooling with those tiny fans on my MB chipset. It's an area of potential failure that I don't want to deal with, and all x570 boards I looked at have active cooling for the chipset.

Anyway, Kudos to AMD and their partners for supporting the new CPUs all the way back to the x370 boards. It's very nice to have the option to keep using my existing MB...and without a significant performance deficit.

Regards,
SB

 

I'm currently running my Ryzen 7 3700X on a Gigabyte Aorus AX370 Gaming 5, runs fine but boosts only around 4,2 GHz on this BIOS and stock cooler. Got new mobo (Asus Prime X570 Pro) waiting already and will install my AiO when I jump over to that mobo, but still waiting for my RX 5700 XT Pulse before I make the jump (because I'm going to do clean install when I get all the pieces together).

Does just cloning a drive work for boot drives? I'm probably going to get Samsung PCIe4 NVMe SSD as soon as the consumer variants are out, and wouldn't want to do another clean install at that point

 

It will work just fine. Samsung offers a free application just for that kind of migration on their site.

 

Just make sure it's software that can clone boot drives.

Reading on reddit and overclock.net, people with my board are able to get 4.4 single core, 4.3 multiple core, and 4.2 or 4.1 all core boost clocks with some tweaks.

So it's possible with x370, but likely not as plug and play as with an x570 board.

Regards,
SB