Intel Arc A380 extreme overclocking is tricky
SkatterBencher purchased an Intel Arc A380 GPU from a Chinese website a few weeks ago. You rushed to overclock your card to a maximum of 3.1 GHz, but the process is much more complicated than it should be.
First, the only overclocking tool available is the official Arc Control software, which provides very basic functionality and little explanation of how to use it. The reviewer ended up looking at the driver code to see what the OC click percentage slide actually does, only to discover that it ends at 2450 MHz for the default voltage-frequency curve.
Discrete Intel Arc GPUs have two overclocking modes: Shift Mode and Lock Mode, the former works similarly to NVIDIA graphics, increasing the maximum frequency with a higher voltage. The latter allows for manual voltage and frequency changes and overrides the 2450 MHz maximum frequency.
Built-in options like Arc Control’s “GPU Performance Boost” are a percentage slider that doesn’t scale as it should (30% boost with slide is 10% higher than clocked at 2696MHz). The GPU Voltage slider doesn’t actually work and there are no memory overclocking tools available.
For that reason, SkatterBencher and Shamino came up with their own tool, which will not be made public for now. This program can override the settings and increase the clocks and voltages much more. In fact, the overclocker even noticed that he accidentally increased the GPU voltage to 2V at some point, which the card apparently survived.
While this tool overcomes the problem of limited overclocking settings, there is still a problem of built-in power limits. Intel Arc A-Series GPUs have PL1 (long term), PL2 (short term), and PL4 (peak) power limits built in, just like CPUs. For A380 the default PL1/PL2 limit is 65.5W and can be increased to 97.5W via Arc Control. These limitations do not apply to custom tools created by SkatterBencher, here the PL1 level can be increased to 298 W and PL2 to 395 W.
Unfortunately, it’s not the PL1 and PL2 levels that are important to SkatterBencher. It is the PL4 limit built into the drivers and set to 800W, which prevents it from finishing the 3.1GHz overclocking attempt. Once the power limit is activated, the clock speed drops to 2.3GHz. So the card reaches this frequency, but does not stay at this frequency level for long.
SkatterBencher is currently evaluating options to modify the PL4 limit, but to no avail so far. It seems that this low-end A380 GPU is not prone to bypass modification, and also the voltage controller data cannot be modified at this point. The PL4 software modification only allows to decrease the power instead of adjusting it further.
With the help of the community and other overclockers, SkatterBencher will likely resolve this issue over time, but one shouldn’t expect Arc GPUs to run at a stable 3.1GHz anytime soon. At least not until higher-end models with much higher power limits are released.
[SkatterBencher] Update on my 3.1 GHz Intel Arc A380 (865 hits)