Master overclocker SkatterBencher on YouTube recently took on the task of overclocking Intel's new Arc A380 GPU in a recent video. However, complications related to Intel's immature drivers and power limits are giving him issues and preventing him from successfully overclocking the GPU.
According to SkatterBencher, Intel's official overclocking driver controls are very primitive and do not provide as much functionality as their Nvidia and AMD counterparts. One example is the GPU clock slider, which adjusts GPU frequency on a percentage basis instead of a static GPU clock offset. Ironically, even the percentages are off. For instance, setting a 30% to overclock via the slider translates into a real-world frequency boost of just 10% on the Arc A380.
To fix this, the overclocker uses a third-party Arc overclocking utility to bypass all limitations with Intel's Arc control panel. However, he has neglected to share the software online since it is brand new and doesn't feature significant safety limitations right now, such as voltage limits.
But, SkatterBencher's biggest issue is the Arc A380's power limits and associated driver limitations. For reference, Intel's Arc GPUs have three power limits in total, including PL1, PL2, and PL4. All feature similar characteristics to Intel's modern CPU architectures.
PL1 is the sustained power limit designed for all workloads with an infinite duration. PL2 is for short workloads that will spike the GPU load temporarily and allows the GPU to push higher voltages temporarily to get that work done more quickly. But the PL4 limit behaves far differently and acts more as an overvoltage/overcurrent protection limit than anything else. PL4 has a maximum wattage rating of 800W, which cannot be bypassed no matter what or manually manipulated in overclocking software (including the unidentified third-party application).
Strangely, SkatterBencher is having issues with the PL4 limit and for some reason, hitting a core frequency substantially higher than the GPU's default core clock - like 3.1 GHz forces PL4 to enable itself, causing the GPU driver to downclock the core below 2.3 GHz.
SkatterBencher doesn't divulge why PL4 is enabling itself in the first place, but it appears to be a bug with Intel's driver package. A 75W Arc A380 shouldn't be capable of hitting 800W even with transients considered. In his video, SkatterBencher discusses three ways he can try and override the PL4 limitations with the Arc A380. But he says it will take some time before he figures out which method will work.
We aren't surprised at these findings; Intel's Arc-focused drivers are already buggy and immature. We suspect it will take Intel a few months before we see better support for overclocking on Arc Alchemist. Unfortunately, Intel is already busy fixing bugs that affect Arc Alchemist's stability under normal conditions, so Intel may not be prioritizing overclocking fixes right now.
It really makes no sense to me that they would abandon ARC expecially after being multiple Billion deep, they need it even more with the disaggregate strategy (Chip stacking/colocating) in order to compete with the likes of Apple and AMD at the power efficient space.