Intel Core i9 9900KF CPU Review

David_Schroth

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We happened upon a processor that doesn't get much press but we see for sale in e-tail, so we did what any reasonable review site would do and strapped the Intel Core i9 9900KF CPU to our test bench.
 
So much for those claims the "dark silicon" would make it a better overclocker. It's just the same CPU either way with the same silicon lottery.
 
I have heard that many people have seen 5.1GHz out of these chips, but that obviously wasn't my experience here. This CPU can do 5.1GHz most of the time, but only in lightly threaded workloads or even gaming. When you push it, the result is the same as it is for the 9900K. It runs out of thermal headroom. This has been the case with all the latest Intel CPU's I've tested. The 9900K, KF, 9700K, and 10980XE are all that way. You can boot them up to 5.1, 5.2GHz, etc. and they'll POST, get into Windows and even do basic stuff.

The problem is that you don't have enough thermal headroom to give them the voltage they need to stabilize at those speeds. The Core i9 10980XE is the most egregious example of this. It's cores all seemed capable of achieving incredible clocks, but you couldn't cool it well enough to do it. You could get through the bulk of our testing suite upwards of 4.9GHz, but it got too hot at the voltages needed to keep it stable.
 
I have heard that many people have seen 5.1GHz out of these chips, but that obviously wasn't my experience here. This CPU can do 5.1GHz most of the time, but only in lightly threaded workloads or even gaming. When you push it, the result is the same as it is for the 9900K. It runs out of thermal headroom. This has been the case with all the latest Intel CPU's I've tested. The 9900K, KF, 9700K, and 10980XE are all that way. You can boot them up to 5.1, 5.2GHz, etc. and they'll POST, get into Windows and even do basic stuff.

Snip
Same with my 4790K I'm able to get into Windows at 5ghz but it never can run cinebench threaded.
 
Same with my 4790K I'm able to get into Windows at 5ghz but it never can run cinebench threaded.

That was a super disappointing CPU. Intel again promised a return 5.0GHz overclocks, but I can't recall any reviews actually achieving that. I'm sure there are outliers that might have been able to get that, but by in large those CPU's weren't the overclocking monsters Intel made them out to be.
 
That was a super disappointing CPU. Intel again promised a return 5.0GHz overclocks, but I can't recall any reviews actually achieving that. I'm sure there are outliers that might have been able to get that, but by in large those CPU's weren't the overclocking monsters Intel made them out to be.
It was a nice CPU, just couldn't live up to the hype. Had Intel not hyped up that 5.0 on air BS I think it would have been much better received. It’s still a very capable CPU today.
 
It was a nice CPU, just couldn't live up to the hype. Had Intel not hyped up that 5.0 on air BS I think it would have been much better received. It’s still a very capable CPU today.

That's my point. It was the fastest gaming CPU on the planet at the time. You can't hate that. But, as you said, it didn't live up to the hype. It was marginally better than the 4770K it replaced.
 
I don't see mentioned in the review what cooling you were using.

Would custom water have helped?
 
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I don't see mentioned in the review what cooling you were using.

Would custom water have helped?

That's an error on my part. I am using custom water cooling on the test bench. It's the same setup I use in the motherboard reviews. It's a Koolance Exos 2.5 (360 radiator) with a Koolance CPU-390 water block. It's the same as using any 360 radiator and water block. The pump is a DD5 (I believe) etc.

I used this same cooler, albeit with a different block to tame the Threadripper 2990WX.
 
Thanks for the review Dan! While not at a price-point match, I would like to have seen the AMD 3700X or even the 3800X in comparison to this one (Matches a core-to-core count). That's my only critique. Overall, great review as usual Dan!
 
Thanks for the review Dan! While not at a price-point match, I would like to have seen the AMD 3700X or even the 3800X in comparison to this one (Matches a core-to-core count). That's my only critique. Overall, great review as usual Dan!

Fair enough. I stuck mostly to price point and to be frank, doing those graphs is a massive pain in the ***. They had gotten out of hand with results, so I cut them down to make them easier to read, and I stuck to the general price point. I will keep that in mind going forward. A core / thread parity comparison is certainly warranted. Good news is, the tests are basically the same (minus one or two added tests) on the 3700X review I did awhile back. So you can make pretty direct comparisons.

The biggest issue being one was tested on 1903 while the other on 1909. I do not think that makes a big difference. If anything, it hurts Intel to be on 1909 as more mitigation patches are likely built into it.

I will say, that my 3950X review will be better on that front because the Intel Core i9 10980XE and 9900KF etc. will be in that. I'm looking forward to seeing the 10980XE vs. the 3950X. I have an idea of how that will shape up, but I'll have to see how it really shakes out when I put all the data together.
 
Thanks for the 9900KFCpu review! It was finger lickin' good! I see no issue with Intel selling these "defective" chips for a little less. I'd consider it for myself if I was in the market. I was rooting for 5.1ghz stable or more, but the 5.0 isn't necessarily a deal breaker. Now if it couldn't hit 5.0ghz, then we'd have something to talk about. Looking forward to more cpu reviews.
 
Thanks for the 9900KFCpu review! It was finger lickin' good! I see no issue with Intel selling these "defective" chips for a little less. I'd consider it for myself if I was in the market. I was rooting for 5.1ghz stable or more, but the 5.0 isn't necessarily a deal breaker. Now if it couldn't hit 5.0ghz, then we'd have something to talk about. Looking forward to more cpu reviews.

More are coming. :)
 
Thanks for the review. An interesting beast and I was a little surprised it couldn't separate itself more from it's counterparts. When I built my 2600k rig I tinkered with the igpu and using virtru. Ultimately a pia and just stayed after with dgpu after that. Kinda bummed this didn't perform better.
 
As I said, some people claim 5.1GHz on these but I didn't see it. I threw it on the Maximus XI APEX which gave it the best possible shot at achieving that speed.
 
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