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.

 

[igor_kavinski]

Why aren't they putting the iGPU in a separate die? Latency?

 

[igor_kavinski]

My understanding is that 5500U/5700U didn't sell all that well so OEMs don't wanna take a risk on the Zen 3 parts. It this is true, it doesn't bode well for the 6000 series from an availability perspective.

 

[Bigos]

Another useless notebook with only 16GB of RAM. That's too little for 8 cores (I care about compilation).

 

[Abwx]

An interesting graph at WCCFTech, RMB should be in the same ballpark a s the 5800U.

AMD Zen 3 Has The Fastest CPU Boost Frequency Ramp Time Of All Chips, Less Than 2ms For Boost To Kick-In

The Zen 3 architecture from AMD has been tested in various applications and achieves its boost clock at lightning-fast rates.

wccftech.com

 

[Bigos]

An interesting graph at WCCFTech, RMB should be in the same ballpark a s the 5800U.

AMD Zen 3 Has The Fastest CPU Boost Frequency Ramp Time Of All Chips, Less Than 2ms For Boost To Kick-In

The Zen 3 architecture from AMD has been tested in various applications and achieves its boost clock at lightning-fast rates.

wccftech.com

"At WCCFTech".

Please link the original source:

https://chipsandcheese.com/2022/09/15/how-quickly-do-cpus-change-clock-speeds/

Also note that the 5800U sample did not boost all the way to its advertised one-core turbo frequency. I only reached 3.7Ghz out of 4.4GHz. I would take the result with a grain of salt then.

 

[mikk]

That assume Vega scales linearly with CUs, and we know from testing the lower CU ones it doesn't.

RDNA2 is about perf/watt.

Still 71% is 71%. 40% faster than the Iris Xe G7 which was the previous fastest so very respectable and Intel has no answer until Meteorlake.

71% against DDR4 Vega8 to be exact. I think it shows that Vega (despite the bad reputation at times) was fine for the lower CU variants on iGPUs and RDNA2 is not a game changer. Intel has no answer (which I think is not a big problem because of the poor SKU adoption of Rembrandt-U), against a 192EUs Xe HPG based GPU AMD needs another big improvement next year to stay in touch for sure. Intel with a TSMC 3nm tile has a big advantage as AMD is likely to use 5nm in 2023. Xe HPG also should solve the mediocre clock speeds of Xe LP (+the mediocre perf/watt....DG2 on TSMC 6nm is reportedly 50% more efficient). Intel expects they have the graphics leadership with Meteor Lake and Arrow Lake.