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0 pointsgiantg21y ago0 comments

Yeah, the 20 core Intels are benchmarking about the same as the 12 core AMD X3Ds. But many people just see 20>12. Either one is more than fine for most people.

"Oh wait, it's really an 8 core when it comes to performance [cores]". So yes, should not be an 8 core all together, but like you said about 14 cores, or 12 with the 3D cache.

"And I doubt those cores have a higher clock."

I'm not sure what we're comparing them to. They should be capable of higher clock than the E cores. I thought all the AMD cores had the ability to hit the max frequency (but not necessarily at the same time). And some of the cores might not be able to take advantage of the 3D cache, but that doesn't limit their frequency, from my understanding.

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hellotomyrars1y ago

It’s kind of funny and reminiscent of the AMD bulldozer days where they had a ton of cores compared to the contemporary Intel chips, especially at low/mid price points but the AMD chips were laughably underwhelming for single core performance which was even more important then.

I can’t speak to the Intel chips because I’ve been out of the Intel game for a long time but my 5700X3D does seem to happily run all cores at max clock speed.

Dylan168071y ago

> I'm not sure what we're comparing them to. They should be capable of higher clock than the E cores.

Oh, just higher clocked than the E cores. Yeah that's true, but if you're using that many cores at once you probably only care about total speed.

You said 12 core with higher clock versus 8, so I thought you were comparing to the performance cores.

> I thought all the AMD cores had the ability to hit the max frequency (but not necessarily at the same time).

The cores under the 3D cache have a notable clock penalty on existing CPUs.

> And some of the cores might not be able to take advantage of the 3D cache, but that doesn't limit their frequency, from my understanding.

Right, but my point is it's misleading to call out higher core count and the advantages of 3D stacking. The 3D stacking mostly benefits the cores it's on top of, which is 6-8 of them on existing CPUs.

giantg2OP1y ago

"The cores under the 3D cache have a notable clock penalty on existing CPUs."

Interesting. I can't find any info on that. It seems that makes sense though since the 7900X is 50 TDP higher than the 7900X3D.

"Right, but my point is it's misleading to call out higher core count and the advantages of 3D stacking"

Yeah, that makes sense. I didn't realize there was a clock penalty on some of the cores with the 3D cache and that only some cores could use it.

LtdJorge1y ago

It's due to the stacked cache being harder to cool and not supporting as high of a voltage. So the 3D CCD clocks lower, but for some workloads it's still faster (mainly ones dealing with large buffers, like games, most compute heavy benchmarks fit in normal caches and the non 3D V-Cache variants take the win).

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