Summary
This issue is currently under investigation.
Description
GPU Voltage value shown in Arc Control's Performance telemetry overlay is capped at 1000 mV and does not reflect the real voltage when it's beyond 1000 mV. If you use HWiNFO to monitor the GPU stats, the hardware reports the correct value of GPU voltage, and HWiNFO can retrieve it.
Resolution
This is a known issue in Intel Arc Control. Check back later.