Question AMD Rembrandt/Zen 3+ APU Speculation and Discussion

[izaic3]

Alright, so we've had some leaks so far. I don't know if any of it's been confirmed yet, as it's pretty early, but here is what I've surmised so far (massive grain of salt of course):

• Zen 3 "enhanced"
• DDR5 and LPDDR5 support
• PCIE4
• 6nm
• CVML
• Navi 2/RDNA/RDNA 2
• 12 CU
• Socket FP7/AM5
• Possible USB4
• 2021(unlikely) -2022 (more likely) release date

If if turns out to have RDNA 2 and 12 CU, I could see iGPU performance potentially almost doubling over Cezanne.

If I've made any mistakes or gotten anything wrong, please let me know. I'd also love to hear more knowledgeable people weigh in on their expectations.

 

[jpiniero]

Don't know if anyone mentioned this but AMD said AM5 is now H2 for sure. It probally makes sense assuming AM5 only supports DDR5 but it also means that the time gap between when Rembrandt becomes available to DIY and Raphael is going to be pretty short.

 

[eek2121]

seems to be a lot of controversy over rembrandt but i am very pleased at what was revealed yesterday. as long as the pricing is in line & there is good availability (along with igpu only options of course!) i don't see how this is not a major win for both AMD & consumers. i am looking forward to the in game benchmarks coming out in the next few months & will certainly be waiting for a memorial day/labor day sale to snag a 15" 6800U to replace my current 4500U (which i hope to sell for $250-300 to help offset the cost of the new laptop).

I don't think there is much controversy, just a couple users raising a big stink. AMD's presentation, for the most part, was great. The only stinker was the lack of more Zen3D SKUs, and the fact Zen3D won't be out until spring.

 

[Thunder 57]

How about this slide? It's my favorite! /s

AMD Socket AM5 "All-New Gaming Platform", as if that's all people use these things for. Wish they had stopped while they were ahead with 5800X3D "Extreme Gaming Performance", at least that one makes sense. After the whole "GameCache" nonsense I'm almost surprised they didn't call it "3D GameCache". Missed opportunity AMD!

Zen 3+ looks good. Zen3D looks confused with a single SKU and Spring launch, especially with the Zen 4 demo they ran. To me it feels like buying a Rocket Lake CPU when Alder Lake came out not much later and blew it away. I'm sure the 5800X3D will sell but it seems like a half-assed effort. I agree with it being used to test the market and low availability due to AMD's server success.

 

[LightningZ71]

For a 5600x3d, it would likely be proced higher than the 5800x, without being much better in most situations. I doubt that it makes sense to sell. For the 5900x3d, I can see that being viable, but, also likely priced too close to the 5950x. The only other SKU that makes sense would be the 5950x3d. They could charge a small fortune for it and sell every one that they make.

As for Rembrandt, I'm very hopeful of the real world performance of the 6800u, but, I feel that it's going to be very pricey. It's going to be difficult to make a value case over any of the 5800u t&ls that have a small dGPU, as the performance won't be much different in practice, and they will be priced in the same range.

As for the 6600u, I don't think that it makes a compelling case over the 5700u (which likely has a faster iGPU and is less expensive) and the likely cheaper 5850u (which will also have a faster iGPU and better CPU performance, especially if combined with LPDDR4x).

 

[ahimsa42]

As for Rembrandt, I'm very hopeful of the real world performance of the 6800u, but, I feel that it's going to be very pricey. It's going to be difficult to make a value case over any of the 5800u t&ls that have a small dGPU, as the performance won't be much different in practice, and they will be priced in the same range.

very true-which is a good indication that there will NOT be a large price premium on the 6800U as if there were AMD would not be selling many units. in ant case, it will likely be more expensive when it initially comes out because it is a new technology but after a few months it will hopefully stabilize & not be much more than a comparable 5800U.

 

[Insert_Nickname]

Zen 3+ looks good. Zen3D looks confused with a single SKU and Spring launch, especially with the Zen 4 demo they ran. To me it feels like buying a Rocket Lake CPU when Alder Lake came out not much later and blew it away. I'm sure the 5800X3D will sell but it seems like a half-assed effort. I agree with it being used to test the market and low availability due to AMD's server success.

If anything, they should market the 5800X3D as an upgrade for Zen+/Zen2 users who already have a board and RAM. As a way to get the most out of your existing platform. It doesn't really make much sense when you already have a 5000-series CPU.

 

[gdansk]

How about this slide? It's my favorite! /s

AMD Socket AM5 "All-New Gaming Platform", as if that's all people use these things for. Wish they had stopped while they were ahead with 5800X3D "Extreme Gaming Performance", at least that one makes sense. After the whole "GameCache" nonsense I'm almost surprised they didn't call it "3D GameCache". Missed opportunity AMD!

Zen 3+ looks good. Zen3D looks confused with a single SKU and Spring launch, especially with the Zen 4 demo they ran. To me it feels like buying a Rocket Lake CPU when Alder Lake came out not much later and blew it away. I'm sure the 5800X3D will sell but it seems like a half-assed effort. I agree with it being used to test the market and low availability due to AMD's server success.

Gaming performance is just code for 1T performance.

But yeah their marketing needs to dial it down a notch.

 

[Thunder 57]

If anything, they should market the 5800X3D as an upgrade for Zen+/Zen2 users who already have a board and RAM. As a way to get the most out of your existing platform. It doesn't really make much sense when you already have a 5000-series CPU.

Certainly a solid upgrade for someone like me on a B450 and 2600X. For my uses I'd go for the 5900X though.

 

[Abwx]

If anything, they should market the 5800X3D as an upgrade for Zen+/Zen2 users who already have a board and RAM. As a way to get the most out of your existing platform. It doesn't really make much sense when you already have a 5000-series CPU.

That s not that big of an upgrade, 5900X/5950X are much more compelling for the purpose.

 

[Shivansps]

At least in my case, i already have a good AM4 board and 32GB DDR4-3600, changing the R5 3600 for something better is a far better choice than being a AM5 early adopter (ive already learned my lesson with AM4) and having to buy expensive and crappy DDR5 rams... whats worse if im need to buy DDR5 i need to buy 64GB, because im not going to buy 32GB again.

So yeah, ill probably end with a 5800X3D or just a plain old 5800X/5900X, and jump to AM5 at around the 3rd gen. And im petty sure im not the only one in this situacion. Raphael needs to blow Zen 3 out of the water to force people with AM4 to upgrade.

 

[The Hardcard]

The interesting take-away is that: Even when operating with a higher 28W max TDP, the 6800U has a longer battery live as the 15W TDP 5800U in a general use case. With all those new power management features, adaptive power management framework and new sleep states it requires less watts over time in the general use case.

View attachment 55479

View attachment 55478

it is not just the interesting take away, in my opinion it is why it was a valid comparison and not deceitful.

More power with no battery trade off? Plus, still no where near the limits of thermal solutions. Even cheap-ass cooling for budget laptops can handle 28W processors throughout their power draw range. If the figures hold up in independent testing, I don’t see how people can feel it was a bad thing to do.

 

[SteinFG]

Since it was leaked by Gigabyte that AM5 processor has 28 PCIe lanes (16 to GPU, 4 to Storage, 4 to chipset, 4 to something general), and it's also known that Rembrandt phisically has 24 PCIe lanes, then what's going to be cut when using Rembrandt on AM5?
a) Gpu slot to X8?
b) chipset to X2 and general to X2?
c) something else
d) Rembrandt won't be on AM5
I'm just curious, because it seems interesting. my feeling is it's going to be option b

 

[leoneazzurro]

Most probably option a) IMO

 

[LightningZ71]

It will likely be either C or D. Both are likely options. I suspect that the chipset link could be x8 for some, or, there will be an option for a second M.2 slot at PCIe 4.0 that isn't active, or becomes SATA only with Rembrandt.

 

[ryanjagtap]

Since it was leaked by Gigabyte that AM5 processor has 28 PCIe lanes (16 to GPU, 4 to Storage, 4 to chipset, 4 to something general), and it's also known that Rembrandt phisically has 24 PCIe lanes, then what's going to be cut when using Rembrandt on AM5?
a) Gpu slot to X8?
b) chipset to X2 and general to X2?
c) something else
d) Rembrandt won't be on AM5
I'm just curious, because it seems interesting. my feeling is it's going to be option b

I hope it's option b as well. Rembrandt is PCIE-4 and cutting lanes for dgpu can cause problems for new upcoming gpus

 

[Joe NYC]

The RX6500XT numbers with 16MB IC and 16 CUs

Supports the idea of RMB IGP with good rams being right at GTX1650 levels. If not TDP limited. And remember, RMB IGP can use up to 8GB VRAM.

Hmm.... Would it be faster than using the LPDDR5 6400?

 

[Shivansps]

Since it was leaked by Gigabyte that AM5 processor has 28 PCIe lanes (16 to GPU, 4 to Storage, 4 to chipset, 4 to something general), and it's also known that Rembrandt phisically has 24 PCIe lanes, then what's going to be cut when using Rembrandt on AM5?
a) Gpu slot to X8?
b) chipset to X2 and general to X2?
c) something else
d) Rembrandt won't be on AM5
I'm just curious, because it seems interesting. my feeling is it's going to be option b

Petty much the same as BR on AM4... A M.2 slot and/or a 2nd/3rd pci-e x16(x4 electrical) for gpu. If OEMs decide to use those extra lanes.

Cutting lanes for main GPU is not going to happen, not even Cezanne/Renoir does that.

 

[Joe NYC]

The interesting take-away is that: Even when operating with a higher 28W max TDP, the 6800U has a longer battery live as the 15W TDP 5800U in a general use case. With all those new power management features, adaptive power management framework and new sleep states it requires less watts over time in the general use case.

View attachment 55479

View attachment 55478

I have to re-watch the presentation, but I think AMD did not stress this point enough. Even though Rembrandt can burst into higher level of performance and uses up some power to get the burst of activity done quickly, it can do all its work on less total battery power used.

So, it is a little bit category bending, which may leave some people confused and underwhelmed from misunderstanding:

28 Watt Rembrandt uses less battery power than 15-Watt competitors. Probably hard to wrap the head around that one for many people...

 

[Shivansps]

Hmm.... Would it be faster than using the LPDDR5?

Well, yes, the RX 6500 XT has about 40GB/s (theoretical, because isnt shared) advantage plus the 16MB IC, 4CU and 200mhz gpu clock.
But that thing is from 23 to 59% faster than the GTX1650 acording to AMD, what is in the GTX1660 non super area, and remember this is a 4GB GPU just like the GTX1650. RMB is not going to have that problem.

I think RMB has a very good chance to land at or just short of the GTX1650, (whiout TDP limits and at least 102GB/s) .

 

[maddie]

Well, yes, the RX 6500 XT has about 40GB/s (theoretical, because isnt shared) advantage plus the 16MB IC, 4CU and 200mhz gpu clock.
But that thing is from 23 to 59% faster than the GTX1650 acording to AMD, what is in the GTX1660 non super area, and remember this is a 4GB GPU just like the GTX1650. RMB is not going to have that problem.

I think RMB has a very good chance to land at or just short of the GTX1650, (whiout TDP limits and at least 102GB/s) .

Rembrandt has no IF cache. Surely this will make the effective memory bandwidth even further apart.

 

[majord]

Nothing scummy about it. AMD increased TDPs this generation to more closely match Intel. Intel’s U chips were 12-28W, AMD decided to do 15-28W.

You read too much into stuff. Rembrant is faster than Cezanne.

You don't have to convince me it's faster. I'm only saying using different cTDP's and claiming twice is fast is a bit scummy that's all. It's just marketing.

 

[flatwhite]

Seriously, no TB4 support for Rembrandt laptops so far from Asus & Lenovo.

 

[Thibsie]

No TB4 is expected IMO
TB3 though shouldnt be hard but it may not be stated so.

 

[uzzi38]

Does anyone think that with the igp and dgpu in AMD advantage laptops being RDNA2, AMD will do something along the lines of Radeon Dual Graphics which it used to have or some other features similar to Intel Deep Link?

The former is dead pretty much, as all mGPU solutions have gone.

I really hope they do something similar to Deep Link though, but we're at the very early stages of AMD making an effort on GPU software looking at how long it took for ROCm Blender support.

 

[uzzi38]

Seriously, no TB4 support for Rembrandt laptops so far from Asus & Lenovo.

Z13 and Z16 both list USB4 support. It's just ASUS that have not said anything about it. Acer have also listed USB4 support on the Nitro 5.