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Comment by simion314 | Hacker News Reader

Probably nobody is saying that AMD is faster, the issue is that if Intel is 5% faster but it costs double(including the coolers) then it does not look that good, so if Intel could find a way to say in the marketing slides that the Intel CPU is up to 50% faster then they can get a lot more sells.

I also read that there are still some controversy about the CPU frequency for multicore and also that reviewers got speical CPUs, you are not guaranteed to get 5GHz on Intel so it is possible that in 1 month the new CPUs will have not as good turbo.

My point is not to rush a purchase based on this initial benchmarks, wait a few more weeks.

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The peak TDP is another controversial point. Interesting page from the Anandtech review:

https://www.anandtech.com/show/13400/intel-9th-gen-core-i9-9...

Fully loading an i9-9900K will consume 170W. Note that this is POV-Ray, a ray tracer, which can be reasonably defined as real-world application.

When stress tests are performed, like the following:

https://www.tomshardware.com/reviews/stress-test-cpu-pc-guid...

the peak is 205W, which is extremely high (when compared to the touted 95W TDP).

AMD is actually transparent on the ThreadRipper power requirements - the reported TDP is 180W, and stress tests confirm that value for several models. In this respect, Intel is arguably cheating. I wonder if AMD could get an advantage (marketing and benchmark-wise), by declaring a low TDP of 95W, while having an effective 200+ one.

Intel has been fudging TDP for years at this point, especially in mobile, but apparently on desktop now, too. If you dissipate the spec sheet TDP, you get spec sheet performance with short turbo boosts, if you can source enough power and dissipate the heat, turbo will stay on. I'm sort of surprised that it peaks at just over twice the spec sheet, though.

Additionally, that hypothetical 5% is observed only in synthetic benchmarks devised to redline the CPU. Thus the performance difference is rather irrelevant and thus the price/performance ratio tilts rather favourably in favour of AMD.

It's not only synthetic benchmarks. Compilation speed improvement is very real, rendering speed, some simulations, etc. If your workloads are very light, you don't need K-class CPU at all. That said, ThreadRipper should be even better for those tasks at similar price and provides additional features like ECC support, more PCI lanes.

IMO 9900K is awesome if you need best in class single-thread performance for one task and good multithread performance for another task. It would be good for me, for example. I like to play WoW and this game is pretty much single-core limited to provide even 60 FPS. And I'm using my PC for development, so improvements for compilation time are nice as well. Whether I would want to pay that price is another matter, I definitely won't buy new Intel CPU until they fix those Meltdown issues causing significant slowdown in some tasks. And if AMD will reach 5+ GHz by that time, I'll happily switch without second thought.

I agree, Intel is faster, what we complained here is the misleading benchmarks and tactics to make the huge price more justifiable.

In programming community Intel also receives more skepticism because their compiler intentionally cripples AMD users and the disclaimer is put on the web as an image so is not picked up by search engines(last time I checked a few months back was still image).

These companies must know how reviewers work. I feel like it is easily gameable. You only have to make sure the first batches on shelves are the real deal. The good reviews flow in and then you can start sending out that high margin stock. What reviewer in their right mind waits until the dust settles and then compares batches?

Has this ever been observed?

https://www.extremetech.com/extreme/184253-ssd-shadiness-kin...

It has with SSDs.

Shady indeed.

Intel should be around 10-15% faster. It's like 4.3 GHz for AMD, 5 GHz for Intel with comparable IPC. Also 5 GHz boost is in 9900K specs, if you're not getting it, it should be enough reason to replace is as a defective.

OK, so I can't be 100%sure what this means: "Max turbo frequency is the maximum single core frequency at which the processor is capable of operating using Intel® Turbo Boost Technology and, if present, Intel® Thermal Velocity Boost. Frequency is measured in gigahertz (GHz), or billion cycles per second."

Does this mean that is guarantedd that 1 core will reach 5GHz ? Are there exceptions? Will it work it regular coolers ? Will it turbo without BIOS changes so in default config?

Thanks if you can clear this, because I am not sure if thix Max is considering power users that overclock or not

I'm not an expert, so take my words with a grain of salt. 9900K will reach 5GHz for 2 cores. So if your OS uses only 2 cores at the same time, they'll work at 5 GHz. If your OS uses more cores, CPU will slow down frequency. Also if CPU will be boosted for too long, it'll slow down anyway, because it must keep its 95W TDP. But you can change setting in BIOS, something like MultiCore Enhancement. This will allow CPU to use as much power as possibe, so it should be able to keep working at 5 GHz and 2 cores, if your PSU and cooler are good enough to provide and dissipate that power.

The i9-9900k should reach 5GHz as long as:

1. Your power supply can supply the 200W needed.

2. Your motherboard's VRMs (voltage regulator modules) can supply the 200W needed.

3. Your CPU coolers can extract 200W of heat.

Its all running outside of Intel's 95W TDP specification, but it seems like Intel is comfortable with claiming 5GHz on 2-cores of the i9-9900k if you have the appropriate PSU / Mobo / Coolers.

All of this is thermally limited. If your cooling system can pull the heat away fast enough, for some period of time the chip will go up to 5GHz on two cores.

It's quite likely that a normal air-moving fan + heatpipe radiator will not let you do this for more than a few minutes.

The 8086k was 1-core 5ghz turbo. 9900k will do it with two.

And it OCs to 5.1 on all cores.

Also for Intel you almost always have to get a new motherboard.

Not now, you can use old Z370.

If your existing board can actually provide enough power to run the chip properly, since clamping it to 95 watts really screws up the performance.

It's probably one of the few cases where you can reuse the chipset / socket though (at least compared to AMD).

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