Comment 1 for bug 1543046

This not not the only existing issue, and flooding journalctl.
Looks like thermald does not check for valid cpu model to avoid that spamming: mine is an old intel q9550, and journalctl has logged:

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thermald[791]: NO RAPL sysfs present
Feb 08 07:16:23 u64 thermald[791]: 10 CPUID levels; family:model:stepping 0x6:17:7 (6:23:7)
Feb 08 07:16:23 u64 thermald[791]: Need Linux PowerCap sysfs
Feb 08 07:16:23 u64 thermald[791]: failed to open /dev/acpi_thermal_rel
Feb 08 07:16:23 u64 thermald[791]: failed to open /dev/acpi_thermal_rel
Feb 08 07:16:23 u64 thermald[791]: TRT/ART read failed
...
...
Unsupported cpu model, use thermal-conf.xml file or run with --ignore-cpuid-check
THD engine start failed
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So thermal-conf.xml might be completed to blacklist some incompatible hardware i suppose.