Question Raptor Lake - Official Thread

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Hulk

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Since we already have the first Raptor Lake leak I'm thinking it should have it's own thread.
What do we know so far?
From Anandtech's Intel Process Roadmap articles from July:

Built on Intel 7 with upgraded FinFET
10-15% PPW (performance-per-watt)
Last non-tiled consumer CPU as Meteor Lake will be tiled

I'm guessing this will be a minor update to ADL with just a few microarchitecture changes to the cores. The larger change will be the new process refinement allowing 8+16 at the top of the stack.

Will it work with current z690 motherboards? If yes then that could be a major selling point for people to move to ADL rather than wait.
 
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Mopetar

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Do you think it will be a bloodbath for Zen 4 3D vs Raptor Lake in gaming or a close win for AMD more often than not assuming paired with GeForce RTX 4090 at 1440p.

Outside of a few titles where the extra cache doesn't do anything for performance, a Zen 4D (I'm too lazy to write Zen 4 3D repeatedly, so I'm just going to call it that despite its lack of temporal die stacking) is going to slaughter anything else. We already know that the 4090 is CPU bound in several titles at 1440p and that's where the v-cache will shine most.

If AMD figured out how to alleviate the voltage limitations that restricted the 5800X3D's clock speed then it's even worse. There will probably still be a few titles where Intel does better, but I don't expect the wins to be a big as where Zen 4D does better.

There's also the question of cost. Zen 3D offered some of the best results for less than a top end AMD or Intel chip. AMD left an obvious price hole in their lineup for Zen 4D and it's likely going to be cheaper than whatever souped up i9 Intel releases that offers their best performance. Never mind that AM5 had an upgrade path so you won't need a new board if you want to get a Zen 5D at some point.
 
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Wolverine2349

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Outside of a few titles where the extra cache doesn't do anything for performance, a Zen 4D (I'm too lazy to write Zen 4 3D repeatedly, so I'm just going to call it that despite its lack of temporal die stacking) is going to slaughter anything else. We already know that the 4090 is CPU bound in several titles at 1440p and that's where the v-cache will shine most.

If AMD figured out how to alleviate the voltage limitations that restricted the 5800X3D's clock speed then it's even worse. There will probably still be a few titles where Intel does better, but I don't expect the wins to be a big as where Zen 4D does better.

There's also the question of cost. Zen 3D offered some of the best results for less than a top end AMD or Intel chip. AMD left an obvious price hole in their lineup for Zen 4D and it's likely going to be cheaper than whatever souped up i9 Intel releases that offers their best performance. Never mind that AM5 had an upgrade path so you won't need a new board if you want to get a Zen 5D at some point.


Yeah if true it makes me wonder why oh why is AMD not releasing Zen 4 3D cache chip right now or within a couple of weeks given the RTX 4090 is hitting retail tomorrow.

I mean it almost seems like any CPU will bottleneck an RTX 4090 even at 1440P or possibly even 4K except the Zen 4 3d Cache versions. Why is NVIDIA even releasing there super GPU if every CPU currently out is going to bottleneck it and Intel and AMD cannot come up with anything better at time of launch to not bottleneck that awesome RTX 4090 at 1440P.
 

Carfax83

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Yes. We saw how well the 5800X3D did in comparison, and that was with lower clocks than the regular Zen 3 CPUs. Given how soon after the launch of Zen 4 we're getting the 3D version it's pretty safe to assume that AMD has things well in hand.

I think it's erroneous to assume that Zen 4 3d is going to scale with V-cache the way that Zen 3D did. Zen 4 has more cache as a baseline, plus it uses DDR5 which provides much more memory level parallelism and bandwidth.

That is going to dampen the impact of the V-cache.
 

Kryohi

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Yeah if true it makes me wonder why oh why is AMD not releasing Zen 4 3D cache chip right now or within a couple of weeks given the RTX 4090 is hitting retail tomorrow.

Because they can't. IIRC TSMC said that production of 6N stacked on 5N chips would start Q4 2022, so it's likely starting only now.
 
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Wolverine2349

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Because they can't. IIRC TSMC said that production of 6N stacked on 5N chips would start Q4 2022, so it's likely starting only now.


Yeah kind of sucks cause if Zen 4 3d Cache is as good as we think, I oh so want t o put a system together with it right as 4090 hits and not wait lol.

If only Intel also had a 3D cache version of Raptor Lake.
 

Carfax83

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Moore's Law is Dead seems to disagree. How would AMD do it if the problem with Zen 3 that the 3D cache boosted was memory bandwidth and that was solved by extra cache?? Where as Zen 4 has much better DDR5 bandwidth and RAM controller so you think it will not scale nearly as well as Zen 3 3D cache did.

MLID is hardly a reliable source, especially when it comes to AMD related leaks. That said, the purpose of cache is to mitigate the latency and bandwidth penalties associated with accessing main memory. CPUs with slower main memory should theoretically benefit more from increased cache than a CPU with faster memory.

I know that Zen 3 3D didn't benefit from memory overclocking as much as standard Zen 3 did, because it had a much bigger L3 cache.

Similarly, Raptor Lake's ability to utilize much higher DDR5 memory speeds than Zen 4 3D should help to compensate somewhat for the smaller L3 cache.

DDR5 memory kits with 7ghz+ speeds are already going to be available later this month.
 
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biostud

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I think it's erroneous to assume that Zen 4 3d is going to scale with V-cache the way that Zen 3D did. Zen 4 has more cache as a baseline, plus it uses DDR5 which provides much more memory level parallelism and bandwidth.

That is going to dampen the impact of the V-cache.
the vcache on 5800X3D gave between 0-40% increased fps over the regular 5800X (with lower clocks) and varied a lot depending on the game. So maybe we will see something like 0-30% compared to the 7700X as I think it will be running at least the same clock as the 7700X. But the average of many games might be lower than the ~15% the 5800X3D was promoted with. It all depends on which games you play.
 
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Shivansps

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I know no one is interested in it for the IGP, but...
DDR5-5200

Stock
3gj8YbL.png

Dv3rjCM.png


2100mhz (the max allowed in the bios)
UqcvpVD.png

P5Z9bTg.png


Its not that bad of a result, definately better than what AMD has on Ryzen 7000X. DDR4-3600 was just 1fps less. It is around 3200G stock performance i belive for Shadow, and W3 is around 5600G perf.
I dont know whats up with W3 1C usage
 

maddie

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MLID is hardly a reliable source, especially when it comes to AMD related leaks. That said, the purpose of cache is to mitigate the latency and bandwidth penalties associated with accessing main memory. CPUs with slower main memory should theoretically benefit more from increased cache than a CPU with faster memory.

I know that Zen 3 3D didn't benefit from memory overclocking as much as standard Zen 3 did, because it had a much bigger L3 cache.

Similarly, Raptor Lake's ability to utilize much higher DDR5 memory speeds than Zen 4 3D should help to compensate somewhat for the smaller L3 cache.

DDR5 memory kits with 7ghz+ speeds are already going to be available later this month.
Is it memory speed or latency that matters when applied to V-cache improvements in performance? Faster memory generally do not improve latency, as faster has higher C#, leading to little to none absolute improvements in latency.
 

Wolverine2349

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Oct 9, 2022
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MLID is hardly a reliable source, especially when it comes to AMD related leaks. That said, the purpose of cache is to mitigate the latency and bandwidth penalties associated with accessing main memory. CPUs with slower main memory should theoretically benefit more from increased cache than a CPU with faster memory.

I know that Zen 3 3D didn't benefit from memory overclocking as much as standard Zen 3 did, because it had a much bigger L3 cache.

Similarly, Raptor Lake's ability to utilize much higher DDR5 memory speeds than Zen 4 3D should help to compensate somewhat for the smaller L3 cache.

DDR5 memory kits with 7ghz+ speeds are already going to be available later this month.


So would having less L3 cache say 16MB instead of 32MB be mitigated by faster RAM on Zen 3. Or is that different as Zen 3 is designed for 32MB cache where as adding 64MB on top is niche and specialized app and does not benefit in all cases?? But 32MB is required for good performance of Zen 3 regardless of memory speed with faster memory just improving performance but if L3 cache was cut in half performance would be crippled no matter how fast you could tune the system RAM?? But different with 96MB as it is a niche use case??

I have also heard that the 5800X3D and maybe the 3D versions in general the extra cache provides some type of latency penalty or cuts some bandwidth in half of some sort which can hurt performance in some things even at same clock speeds despite it being good for most games?? Is that true with cache stacking in general and how exactly does that work?? And would it be the same on Zen 4 3D cache versions???
 
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Wolverine2349

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Oct 9, 2022
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I know no one is interested in it for the IGP, but...
DDR5-5200

Stock
3gj8YbL.png

Dv3rjCM.png


2100mhz (the max allowed in the bios)
UqcvpVD.png

P5Z9bTg.png


Its not that bad of a result, definately better than what AMD has on Ryzen 7000X. DDR4-3600 was just 1fps less. It is around 3200G stock performance i belive for Shadow, and W3 is around 5600G perf.
I dont know whats up with W3 1C usage


Is that the 13900K playing Witcher 3 with no discrete GOU and using the integrated graphics. And better than AMD Ryzen 7000? DO you mean Ryzen 7000 with their integrated GPU??

The real test are these CPUs with a 3090 Ti or even better a 4090.
 

Carfax83

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Nov 1, 2010
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Is it memory speed or latency that matters when applied to V-cache improvements in performance?

Not sure I understand what you are asking here as the question is phrased strangely....

Faster memory generally do not improve latency, as faster has higher C#, leading to little to none absolute improvements in latency.

Higher frequency memory does improve both latency and bandwidth. CAS latency only affects memory latency when the memory has to activate a new column. If I remember correctly, CAS stands for column access strobe. Also, DDR5 has other tricks up it's sleeve to reduce effective latency. DDR5's evolution will likely see it max out at around the 8.4ghz for JEDEC standard modules, while much higher for overclocked ones. At those speeds, the effective latency is below 10ns even with a CAS latency of 40.

40/8400x2000= 9.5ns
 

Carfax83

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So would having less L3 cache say 16MB instead of 32MB be mitigated by faster RAM on Zen 3

Absolutely. But there are limitations due to how far away the system memory is from the CPU.

Or is that different as Zen 3 is designed for 32MB cache where as adding 64MB on top is niche and specialized app and does not benefit in all cases?? But 32MB is required for good performance of Zen 3 regardless of memory speed with faster memory just improving performance but if L3 cache was cut in half performance would be crippled no matter how fast you could tune the system RAM?? But different with 96MB as it is a niche use case??

You're overthinking it. Cache is SRAM memory, which is much faster and less capacity than DRAM.

Also cache is built directly next to the CPU cores themselves which drastically reduces access latency.

Even with hyper fast system memory, cache will always have lower latency because of it's proximity to the CPU.

I have also heard that the 5800X3D and maybe the 3D versions in general the extra cache provides some type of latency penalty or cuts some bandwidth in half of some sort which can hurt performance in some things even at same clock speeds despite it being good for most games?? Is that true with cache stacking in general and how exactly does that work?? And would it be the same on Zen 4 3D cache versions???

Increasing the cache capacity does increase latency as it takes longer to access the data, but it's still far less latency than accessing system memory.

That's precisely why V-cache provides such a significant increase in game performance. Anything that gets data to the CPU faster is going to increase performance.
 
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maddie

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Not sure I understand what you are asking here as the question is phrased strangely....



Higher frequency memory does improve both latency and bandwidth. CAS latency only affects memory latency when the memory has to activate a new column. If I remember correctly, CAS stands for column access strobe. Also, DDR5 has other tricks up it's sleeve to reduce effective latency. DDR5's evolution will likely see it max out at around the 8.4ghz for JEDEC standard modules, while much higher for overclocked ones. At those speeds, the effective latency is below 10ns even with a CAS latency of 40.

40/8400x2000= 9.5ns
The ns latency has remained fairly constant as you show and which I clumsily stated. This is what I mean when I said DDR5 does not lower access times by being faster. In programs with a lot of small data package access needed, V-cache will give lots of benefits even though DDR5 has higher bandwidth. That is my claim.
 

Henry swagger

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DrMrLordX

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40k at 290 watts.. dvlr at work 🤔

292W stock? Ew.
 
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nicalandia

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Some people paid around $630 for the pre-orders. There is a chance that the i9-13900K/KF SKUs may get scalped hard, coz 4090 gamers will want the best gaming CPU and a lot of them are bent towards Intel.
Who is to say that the 13900K will be the best for 4090? Does CPU matters at 4K? For Bragging rights at 480p and 720p reviews on Anandtech?