CPU overclocking :
So, considering the temperatures obtained at the original frequency under Cinebench R23, 91°C, while we are under a custom watercooling, the overclocking margin might be quite limited. At the same time, this is also good news as our Ryzen 9 7950X will offer excellent performance from the start. Currently, to overclock our processor, we must either do it directly via the BIOS or via the AMD Ryzen Master software. It is the latter solution that we have chosen for these first tests.
Before starting, it is necessary to have one or more reference scores with your processors at stock frequencies, i.e., without having made any modifications other than having activated the XMP/EXPO profile. It is also very important to have a sheet of paper at hand that will allow you to note all the tests you are going to perform as well as the results or failures. Personally, I have hundreds of sheets of my tests on which I sometimes go back to find out how the processor behaved on a particular motherboard or in a particular test condition. My own little bible.
For H24 overclocking, it will of course be necessary to take more time to fine-tune the voltage in order to provide it with the minimum necessary, but also to adjust each core independently if you want to take advantage of the maximum performance.
Load-Line Calibration :
The idea of modifying the Load Line Calibration is that the voltage chosen should be as close as possible to the load voltage. AORUS offers several levels of “calibration” and we chose the “Turbo” mode. This is the one we used in our previous tests with AORUS motherboards.
Since the motherboard has voltage measurement points on its PCB, we will be able to judge the impact of this setting on the vcore voltage, i.e. the CPU voltage.
Ryzen 9 7950X operation :
For once, we will start our overclocking tests via the OS using AMD Ryzen Master. It is a tool that can be used very easily and is therefore very intuitive provided that you have a good understanding of the structure of your processor and here more particularly that of the Ryzen 9 7950X.
The Ryzen 9 7950X has two CCDs. Each CCD has a single CCX which has 8 cores. In the case of our 7950X, none of the CCX cores are disabled so that there are 8 cores per CCD and therefore 16 in total. The idea is to see how the CCDs behave when all the cores are used. We saw on page 5 that CCD0 performed better than CCD1. It will therefore be possible via Ryzen Master to try to push this one higher than the other.
Finally, you can also decide to vary the frequency of each core. The one with a star is the one that performs best of the 8. To overclock, go to profile 1 and select manual overclocking. This allows you to control either each CCX or each core independently.
Overclocking in different stages :
We will first start testing at 5000 MHz on both CCXs with a voltage of 1.07v which when Cinebench R23 multi is launched is set to 1.14 volt. The idea is then to test the stability on several runs of Cinebench R23 multithread . If it’s stable, I increase the frequency by 100 MHz while rechecking the stability. If the benchmark crashes, I increase the voltage slightly in order to regain stability to run the benchmark. The objective is to get a “quick” idea of the maximum benchmarkable frequency. Here are the results obtained.
We were able to reach 5400 MHz on all 16 cores for a voltage measured with a multimeter of 1.32 volts. The gains are quite minimal since as we said, with a good cooling system, the original performance is already excellent. Thanks to AMD Ryzen Master, you can overclock the cores independently or one CCD higher than the other, which we will show you shortly in the tutorial about overclocking via Ryzen Master.
Finally, and this is great news, it is possible to disable the synchronization between the BCLK frequency and the PCIe frequency via the BIOS. It will now be possible to overclock via the BCLK frequency.