Methodology: temperature and clock speed tests
For completeness of Intel Core i5-14400F processor tests we add the results of its second stepping. We’ve already tested the B0 variant, now it’s time for the C0. Its availability in stores is, at least at the moment, considerably worse and the question arises whether it is worth it at all. Is there any point in aiming for stepping C0 or is B0 also “okay”? Or does it “not matter” (what you get in the shopping lottery)?
Methodology: temperature and clock speed tests
When choosing a cooler, we eventually opted for Noctua NH-U14S. It has a high performance and at the same time there is also the TR4-SP3 variant designed for Threadripper processors. It differs only by the base, the radiator is otherwise the same, so it will be possible to test and compare all processors under the same conditions. The fan on the NH-U14S cooler is set to a maximum speed of 1,535 rpm during all tests.
Measurements always take place on a bench-wall in a wind tunnel which simulates a computer case, with the difference that we have more control over it.
System cooling consists of four Noctua NF-S12A PWM fans, which are in an equilibrium ratio of two at the inlet and two at the outlet. Their speed is set at a fixed 535 rpm, which is a relatively practical speed that is not needed to be exceeded. In short, this should be the optimal configuration based on our tests of various system cooling settings.
It is also important to maintain the same air temperature around the processors. Of course, this also changes with regard to how much heat a particular processor produces, but at the inlet of the tunnel it must always be the same for accurate comparisons. In our air-conditioned test lab, it is currently in the range of 21–21.3 °C.
Maintaining a constant inlet temperature is necessary not only for a proper comparison of processor temperatures, but especially for unbiased performance comparisons. Trend of clock speed and especially single-core boost depends on the temperature. In the summer at higher temperatures, processors may be slower in living spaces than in the winter.
For Intel processors, we register the maximum core temperature for each test, usually of all cores. These maximum values are then averaged and the result is represented by the final value in the graph. From the outputs of single-threaded load, we only pick the registered values from active cores (these are usually two and alternate during the test). It’s a little different with AMD processors. They don’t have temperature sensors for every core. In order for the procedure to be as methodically as possible similar to that applied on Intel processors, the average temperature of all cores is defined by the highest value reported by the CPU Tdie sensor (average). For single-threaded load, however, we already use a CPU sensor (Tctl/Tdie), which usually reports a slightly higher value, which better corresponds to the hotspots of one or two cores. But these values as well as the values from all internal sensors must be taken with a grain of salt, the accuracy of the sensors varies across processors.
Clock speed evaluation is more accurate, each core has its own sensor even on AMD processors. Unlike temperatures, we plot average clock speed values during tests in graphs. We monitor the temperature and clock speed of the processor cores in the same tests, in which we also measure the power consumption. And thus, gradually from the lowest load level on the desktop of idle Windows 10, through audio encoding (single-threaded load), gaming load in three games (F1 2020, Shadow of the Tomb Raider and Total War Saga: Troy), to a 10-minute load in Cinebench R23 and the most demanding video encoding with the x264 encoder in HandBrake.
To record the temperatures and clock speed of the processor cores, we use HWiNFO, in which sampling is set to two seconds. With the exception of audio encoding, the graphs always show the averages of all processor cores in terms of temperatures and clock speed. During audio encoding, the values from the loaded core are given.
- Contents
- Intel Core i5-14400F (C0 vs. B0)
- Methodology: performance tests
- Methodology: how we measure power draw
- Methodology: temperature and clock speed tests
- Test setup
- 3DMark
- Assassin’s Creed: Valhalla
- Borderlands 3
- Counter-Strike: GO
- Cyberpunk 2077
- DOOM Eternal
- F1 2020
- Metro Exodus
- Microsoft Flight Simulator
- Shadow of the Tomb Raider
- Total War Saga: Troy
- Overall gaming performance
- Gaming performance per euro
- PCMark and Geekbench
- Web performance
- 3D rendering: Cinebench, Blender, ...
- Video 1/2: Adobe Premiere Pro
- Video 2/2: DaVinci Resolve Studio
- Graphics effects: Adobe After Effects
- Video encoding
- Audio encoding
- Broadcasting (OBS and Xsplit)
- Photos 1/2: Adobe Photoshop and Lightroom
- Photos 2/2: Affinity Photo, Topaz Labs AI Apps, ZPS X, ...
- (De)compression
- (De)encryption
- Numerical computing
- Simulations
- Memory and cache tests
- Processor power draw curve
- Average processor power draw
- Performance per watt
- Achieved CPU clock speed
- CPU temperature
- Conclusion
What is the explanation of the occasional erratic results? For instance, the first results for 3D mark: 14400F performs 6x better there than 14900k (and everything else)! I noticed similar weird results for multiple other tests as well. For example, in several graphics tests (gpu-based?), 12100 was the fastest one.
There may be several reasons. For a deeper analysis it is necessary to have an overview of the activity of all cores and the consumption for specific tests. We have this only for selected tests, for all tests it is impossible with such a large subset (of tests). We do not even do some tests for Intel processors with little and big cores and we do not include them in the graphs, because we know that the processor is not fully loaded and for example only little cores are used (there are boxes with a warning about this in all the result chapters that are concerned). In such cases we would, of course, measure significantly higher speed with the Ci3-12100F (with four P cores) than Ci5-14400F (with four E cores). In some subtests, the behavior with poor utilization of the P cores definitely occurs, and for example this can explain the things you are asking about. But of course there may be more explanations, and it is not possible to deal with every single situation in such a range of tests, and we can only speculate on the results in this way. 🙂
PS: Some, typically very short tests, are also affected by the speed with which a given processor can react to a change in CPU core(s) clock speeds (e.g. in a single-threaded load).