The Intel Core i9-9900K at 95W: Fixing The Power for SFF
by Ian Cutress on November 29, 2018 8:00 AM ESTTest Bed and Setup
As per our processor testing policy, we take a premium category motherboard suitable for the socket, and equip the system with a suitable amount of memory running at the manufacturer's maximum supported frequency. This is also typically run at JEDEC subtimings where possible. It is noted that some users are not keen on this policy, stating that sometimes the maximum supported frequency is quite low, or faster memory is available at a similar price, or that the JEDEC speeds can be prohibitive for performance. While these comments make sense, ultimately very few users apply memory profiles (either XMP or other) as they require interaction with the BIOS, and most users will fall back on JEDEC supported speeds - this includes home users as well as industry who might want to shave off a cent or two from the cost or stay within the margins set by the manufacturer. Where possible, we will extend out testing to include faster memory modules either at the same time as the review or a later date.
Test Setup | |||||
Intel 9th Gen | i9-9900K i7-9700K i5-9600K |
ASRock Z370 Gaming i7** |
P1.70 | TRUE Copper |
Crucial Ballistix 4x8GB DDR4-2666 |
Intel 8th Gen | i7-8086K i7-8700K i5-8600K |
ASRock Z370 Gaming i7 |
P1.70 | TRUE Copper |
Crucial Ballistix 4x8GB DDR4-2666 |
Intel 7th Gen | i7-7700K i5-7600K |
GIGABYTE X170 ECC Extreme |
F21e | Silverstone* AR10-115XS |
G.Skill RipjawsV 2x16GB DDR4-2400 |
Intel 6th Gen | i7-6700K i5-6600K |
GIGABYTE X170 ECC Extreme |
F21e | Silverstone* AR10-115XS |
G.Skill RipjawsV 2x16GB DDR4-2133 |
Intel HEDT | i9-7900X i7-7820X i7-7800X |
ASRock X299 OC Formula |
P1.40 | TRUE Copper |
Crucial Ballistix 4x8GB DDR4-2666 |
AMD 2000 | R7 2700X R5 2600X R5 2500X |
ASRock X370 Gaming K4 |
P4.80 | Wraith Max* | G.Skill SniperX 2x8 GB DDR4-2933 |
GPU | Sapphire RX 460 2GB (CPU Tests) MSI GTX 1080 Gaming 8G (Gaming Tests) |
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PSU | Corsair AX860i Corsair AX1200i |
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SSD | Crucial MX200 1TB | ||||
OS | Windows 10 x64 RS3 1709 Spectre and Meltdown Patched |
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*VRM Supplimented with SST-FHP141-VF 173 CFM fans |
We must thank the following companies for kindly providing hardware for our multiple test beds. Some of this hardware is not in this test bed specifically, but is used in other testing.
101 Comments
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schujj07 - Thursday, November 29, 2018 - link
You are missing the entire point of the article. This is a follow-up to how Intel rates TDP for their CPUs. Intel's TDP is for the base clock only and this was to show what the performance would be if they had TDP meaning the absolute max power draw of the CPU. Right now the i9-9900k uses over 160W of power in its out-of-box configuration that most people use. If you buy a CPU cooler that is rated for say 125W thinking you will be covered since it is a "95W" CPU you will not be getting the performance that you are seeing in professional benchmarks. AMD on the other hand has their TDP being the max power draw of the CPU. Exception being the 2700X that hits like 110W in reviews I have seen. Therefore you buy a 125W cooler for the 2700X you will get the performance you are expecting.4800z - Thursday, November 29, 2018 - link
The 2700x can't go faster even if you gave it more power and a more expensive cooler. No one has been able to materially overclock the 2700x.Hul8 - Thursday, November 29, 2018 - link
It's not about OC, but the experience out of the box.Out of the box, AMD very closely follows TDP, going over by 5 - 10 W at the most.
Intel motherboard manufacturers ignore Intel guidelines and allow the CPU to boost ad infinitum (instead of the Intel spec 8 seconds). This means that *out of the box*, a CPU rated 95 W will require a 145 - 160 W cooler when running 100% on all cores, or it will throttle.
Hul8 - Thursday, November 29, 2018 - link
Obviously once you run a i9 9900K at 150 W, you will definitely get much better performance, but that is contingent on good cooling.Targon - Thursday, November 29, 2018 - link
And you won't get great cooling in a SFF machine.Alexvrb - Friday, November 30, 2018 - link
That's the main point. The reviews and benches all are testing it on "unlimited", which makes it look better than it actually IS when you're TDP-limited.A lesser issue is that when you're NOT TDP limited, it eats a crapton more power, runs hotter, and dumps more heat into your system than you were anticipating based on TDP.
The cake is a lie. I mean TDP.
HStewart - Thursday, November 29, 2018 - link
I would think that people that overclock a system, would understand that running at higher than base clock means that you need a more powerful power supply - plus they like have external GPU that uses a lot power and in a lot cases more than the CPU itself.Hul8 - Thursday, November 29, 2018 - link
Problem here is that it's not the user overclocking the system - it's the motherboard with default UEFI settings increasing Tau to (close to) infinity, thereby allowing the CPU to boost for hours.Beginners won't even be aware that they're not getting the most of their expensive CPU, since there is no way for them to know to anticipate 145 - 160 W of thermal dissipation.
Hul8 - Thursday, November 29, 2018 - link
ASUS is the only motherboard manufacturer whose Z390 boards can be configured to obey the TDP and even there you first need to enable XMP and then select "Intel" instead of "ASUS" in the prompt that appears. If you don't touch XMP (as many beginners are likely to), you'll run with grossly extended Tau out of the box.HStewart - Thursday, November 29, 2018 - link
I would expect if the motherboard company is making the settings higher than recommend from processor company - they should inform the customer they recommend larger power. This assumes I understand the entire motherboard settings of desktop machines lately - it been about slight over 10 years since I built a desktop machine and it was a Supermicro Dual Xeon