Hi everyone,
I’m working with a DGX Spark (Grace GB10) system and I’m trying to access Grace CPU power telemetry, but so far I haven’t been able to find any of the interfaces described in the official Grace Performance Tuning Guide.
Below is a summary of what I’ve verified.
. No ACPI Power Meter / hwmon power sensors
The guide mentions interfaces such as:
-
power1_input -
power1_average -
power1_oem_info
However, on DGX Spark, the hwmon device only exposes thermal‑related fields:
available_policies
emul_temp
integral_cutoff
k_d
k_i
k_po
k_pu
mode
offset
policy
power
slope
sustainable_power
temp
trip_point_0_*
There are no power meter attributes under any hwmon device.
2. No SCMI Power Domain
The directory:
/sys/class/scmi_power/
does not exist or is empty, suggesting SCMI power telemetry is disabled on Spark.
3. ACPI Power Meter appears disabled
The documentation states that Grace CPU power telemetry requires:
-
CONFIG_SENSORS_ACPI_POWER -
Kernel parameter:
acpi_power_meter.force_cap_on=y
But DGX Spark’s kernel does not seem to expose any ACPI power meter device.
4. DCGM / NVML only report GPU power
nvidia-smi and DCGM provide GPU power draw, but no Grace CPU power information.
5. DGX Spark has no BMC
Since Spark lacks a BMC, Redfish/IPMI cannot be used to retrieve CPU rail power either.
My Questions
I would like to confirm the following:
1. Is Grace CPU power telemetry completely disabled on DGX Spark hardware?
2. Is there any kernel configuration, driver module, or DGX OS package that can enable it?
3. Are there hidden sysfs interfaces, NVML/DCGM extensions, or experimental features that expose CPU rail power?
4. Will future DGX OS releases provide Grace CPU power telemetry for Spark?
5. If telemetry is intentionally unavailable, is there an NVIDIA‑recommended alternative for estimating CPU power?