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Comment by leetcrew | Hacker News Reader

this doesn't quite pass the smell test. I can't quite tell if there's a way to filter out results from overclocked parts in geekbench, but it looks like these results for the i9-10900F are significantly lower than typical results for a stock i9-9900K. hard to believe they would do worse on the same process with more cores.

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I think the key thing you've missed is the i9-10900F is a 65W part, while the i9-9900K is 95W.

Given both are on basically the same manufacturing process with basically the same architecture, it's really not surprising the i9-10900F isn't keeping up with the i9-9900K in max load scenarios. Having 50% more power easily makes up for 20% fewer cores.

Which is then also why the 4900HS is able to be so competitive with it. It's a 35W part but on a more advanced manufacturing node.

And although TDP is a made up number that has very little meaning, it is roughly what the CPU will settle into when the boost duration has exceeded. So eventually under a constant multithreaded workload the 9900K and 10900F should settle in to their 95W and 65W limits respectively.

you're right, I confused "F" with "KF".

> And although TDP is a made up number that has very little meaning, it is roughly what the CPU will settle into when the boost duration has exceeded. So eventually under a constant multithreaded workload the 9900K and 10900F should settle in to their 95W and 65W limits respectively.

this part isn't quite true. TDP for intel parts is more like max thermal dissipation at base clocks. most people/OEMs will couple a 9900k with a pretty beefy cooler and set the boost duration to be effectively infinite. in most cases, that part will never hit its base frequency under load. I have a 9700k, and, under the default bios settings for the motherboard, it will happily draw 120-140W indefinitely.

> most people/OEMs will couple a 9900k with a pretty beefy cooler and set the boost duration to be effectively infinite

They will, but that's technically no longer stock. Prebuilt systems from mainstream OEMs are unlikely to be configured like that, especially when we're not talking about the enthusiast line of motherboards.

If the motherboard is following Intel's actually spec for these (which does exist), then it will settle in to the TDP limit after PL2's duration is exceeded, which is supposed to be 8 seconds for Intel's 95W spec.

It is likely that the unnamed HP system with the i9-10900F is at least following Intel's recommended settings here. The 9900K system might very well not be, though, which would then make the power budget gap that much wider.

It is worth noting that this is the i9-10900F, not the i9-10900k (thank you, Intel, for the lovely naming scheme). I'd expect the -k variant to be at least as fast as the i9-9900k.

Not sure how that will matter, F just means there are no integrated graphics. Why would that impact performance compared to a i9-9900 ?

I believe the K variant also has a higher base clock (3.7 vs. 3.2)

Also, 9900 was much easier to say... how do you pronounce 10900? "Ten-thousand-nine-hundred"? Feels tortured. "Ten-nine-hundred"? Yeesh.

Ten-Nine Hundred is what I've seen on YouTube recently and I like it.

It works semantically too. You say the generation first, then the specific model within that generation.

Tenty nine hundred duh

Does Intel ever even use those last two zeroes, or could we start leaving them off and calling this part the "one oh nine"?

They definitely use them, but less often on the i9 series since there isn't a lot of options in that range.

Compare 10th gen i9 to i7:

https://ark.intel.com/content/www/us/en/ark/products/series/...

Ten Nine Hundred scans much better. I'd expect it to be what people settle on. Sort of like the Lockheed L Ten Eleven.

On a related note, how do people pronounce the Intel 8088?

Eight oh eight eight? Eighty eighty eight?

good point, I was confusing the F-suffix with the KF-suffix parts, which usually perform identically to K-suffix parts.

It also doesn't pass the smell test in that the single core performance is higher than the Ryzen 4900 and it also has both more cores and more threads yet it is far behind on multicore performance?

Likely some thread affinity issue that just needs a patch.

At the turbo clock the i9-10900F is 5GHz vs. 4.3Ghz for Ryzen 9 4900HS. At the base clock the i9-10900F is 2.8GHz vs. 3GHz for the Ryzen 9 4900HS.

Basically implies that Ryzen has better performance per watt, which doesn't affect absolute performance until you exhaust the power budget and have to lower the clock speed, i.e. use all the cores instead of just one.

edit: 4900HS, not 4900H

Small nit but the comparison here is against the 4900HS

    4900H:  4.4ghz boost, 3.3ghz base
    4900HS: 4.3ghz boost, 3.0ghz base

With the non-S variant being the more power hungry one with an up to 54W TDP vs. the S's 35W TDP.

Interestingly even the faster 4900H has a lower TDP than the 65W i9-10900F.

Multithreaded applications tend to share a lot of data between threads, and we already know Intel's mesh fabric core interconnect[1] seems to be inferior to AMD's chiplet+io die in terms of performance and access latency uniformity.

[1] used in all 10core+ Intel CPUs.

The 10900 uses a ring and IMO the mesh is superior to Infinity Fabric.

AMD's 4000 APUs are monolithic and don't use separate chiplets and IO die. The chiplet + infinity fabric has higher latency than Intel, but that's not a problem for the APUs.

this part isn't quite as hard for me to believe. intel cores are less efficient than amd cores, so they have to downclock more when more cores are loaded.

throttling

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