- Mar 3, 2017
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If the cost is indeed area and power, then the 8-core having a TDP of 170 W, ie. 230 W PPT means that the 16-core flagship will be power limited if 230 W is the limit of the platform.IPC isn't free, you're paying in area and power.
Every bit as limited as Zen4 one so nothing changes.If the cost is indeed area and power, then the 8-core having a TDP of 170 W, ie. 230 W PPT means that the 16-core flagship will be power limited if 230 W is the limit of the platform.
Are you seriously comparing street prices to SRP?And you're saying that they're gonna charge an almost 100% premium over the 7950X for the 16c, which goes for $550 at the moment.
It doesn't add up.
Oh it's a sucker SKU indeed.I won't even consider a 170W (actually 230W) single CCd design. It'd throttle itself
I don't see why 6 GHz in r23 is impossible given that we assume the rumors to be true. r23 doesn't use much vector math, and AVX/2/512 throttling is mostly solved since Ice Lake.7700X all core AVX clock rate is usually around 5.3GHz. Multiply by 1.15 ≈ 6.1GHz.
6.1GHz all core In an AVX workload like CB r23?
On that idea I call bogus.
It is 'solved' in Zen 4 by dropping clock rates dynamically but only a little. And like most raytracers r23 uses pretty much only SIMD instructions.I don't see why 6 GHz in r23 is impossible given that we assume the rumors to be true. r23 doesn't use much vector math, and AVX/2/512 throttling is mostly solved since Ice Lake.
because this is a very high IPC core.I don't see why 6 GHz in r23 is impossible
bingoit'll always be at 95C limiting itself.
It is 'solved' in Zen 4 by dropping clock rates dynamically but only a little. And like most raytracers r23 uses pretty much only SIMD instructions.
If AMD is doing a sucker 170W 8-core SKU I wager it's only going to get another 2-300MHz over the 16 core version and it'll always be at 95C limiting itself.
Here's what I understand as to putting the "40% core for core" higher performance of Zen 5 in context.because this is a very high IPC core.
It won't clock much higher, but power-frequency scaling can be expected IF and only IF the 8c part is now 170W instead of 105W.I really don't think this is a design that will be clocking much higher but who knows.
Here's what I understand as to putting the "40% core for core" higher performance of Zen 5 in context.
The only way you are going to get close to that figure is by increasing clock speeds AND a new, high-IPC core.
It may be possible to do so by making the 8c part 170W to get more frequency, but for the 16c parts you're not going to get 40% higher performance in something like CB r23 as they are already at 170W.
Unhappy with Cinebench speculation?What will be the Geekbench ST for Zen 5?
Everyone keeps speculating on Cinebench
Let's do some quick estimates:
IN CB r23, Zen 3 to Zen 4 was 9% higher perf at fixed 4 GHz comparing 8 core to 8 core (source).
Now since Zen 5 is rumored to have more gains in the front-end and since r23 is front-end bound, lets assume that under the same conditions Zen 5 is 20% faster than Zen 4.
Now in the actual 8-core SKUs if the new TDP is indeed 170W, then to account for a 62% increase in power, vs 105W, the frequency would have to increase by roughly 15% (power-frequency dependency roughly following cubic relationship).
So 15% frequency increase and 20% ppc increase would put this 8-core Zen 5 ~38% faster than the 8-core 7700X. This is in line with the rumored performance uplift of 40%.
HOWEVER.
This increase is coming partly from increased clocks, which would mean that for the 16c Zen5 and Zen4 parts, which are both 170W, the benefit of the frequency increase will be absent. So, theoretically, in r23, the gain over the 7950X would be 25% at most.
40% higher core for core perf suddenly doesn't seem that impressive when you consider the actual CPUs in question, especially at the high-end.
That is what makes the $1000 rumored price tag for the 9950X for a measly 20-25% gain in CB r23 over the 7950X sus.True or not, the 40+% rumors have been single threaded performance, so power limits won't come into play.
Those figures are almost always obtained using some small reference core like the Cortex A78. Doesn't mean a damn thing in reality when trying to extrapolate to high frequency x86 cores.All this is hugely wrong, because N4P used for Zen 5 has either 11% better perf/isowatt or 22% lower power at isoclock (= 28% higher perf/watt at isoclock) than the N5 used for DT Zen 4.
As was said before, if you want performance, and the best, its not free.Mark, that is you. Take China market which are big market for AMD and Intel, people there are price sensitive. If AMD/Intel price the CPU too high, they won't get much sales. That's why AMD has to adjust Zen4 pricing after two months due to lack of sales.
Why don't you save your arguments until its out, and published benchmarks and reviews are released. Arguing now is kind of pointless.Here's what I understand as to putting the "40% core for core" higher performance of Zen 5 in context.
The only way you are going to get close to that figure is by increasing clock speeds AND a new, high-IPC core.
It may be possible to do so by making the 8c part 170W to get more frequency, but for the 16c parts you're not going to get 40% higher performance in something like CB r23 as they are already at 170W.
That is what makes the $1000 rumored price tag for the 9950X for a measly 20-25% gain in CB r23 over the 7950X sus.
Those figures are almost always obtained using some small reference core like the Cortex A78. Doesn't mean a damn thing in reality when trying to extrapolate to high frequency x86 cores.
Thank you. I'll leave now.Unhappy with Cinebench speculation?
Then let me show you some happy data?
9950X
GeekBench 6
single 3628 more than 23868
GeekBench 5
single 2715 more than 27712
(Only test data, does not represent the final result)
No, as usual you understand very little of how process nodes can be tweaked to account for target PPA which is variable based on the design under consideration.That change nothing, it s a comparison between N5 and N4P/X, the core design is of no importance here, the process perfs and perf/watt difference will be the same whatever the core, if a X86 core get 25% better perf/isowatt when shrinking then a Cortex will also benefit from those 25%/isowatt once shrinked.
That is what makes the $1000 rumored price tag for the 9950X for a measly 20-25% gain in CB r23 over the 7950X sus.
Those figures are almost always obtained using some small reference core like the Cortex A78. Doesn't mean a damn thing in reality when trying to extrapolate to high frequency x86 cores.
I'm not arguing. I'm just trying to make sense of the rumors.Arguing now is kind of pointless.
Well here's a thought, in what cases don't mlid's infos and the rest of the rumor mills actually contradict?Arguing now is kind of pointless.