I discovered that running Speccy on my laptop (Windows 10 Pro 64-bit) causes WMI Provider Host process to constantly use 10-20% CPU (significantly raising temperatures and fan noise).
I see plenty of errors (one every second) in Event Viewer under Applications and Service Logs => Microsoft => Windows => WMI Activity.
Here is the XML dump of the error (they all look the same):
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
<System>
<Provider Name="Microsoft-Windows-WMI-Activity" Guid="{1418EF04-B0B4-4623-BF7E-D74AB47BBDAA}" />
<EventID>5858</EventID>
<Version>0</Version>
<Level>2</Level>
<Task>0</Task>
<Opcode>0</Opcode>
<Keywords>0x4000000000000000</Keywords>
<TimeCreated SystemTime="2017-11-01T15:30:37.753924100Z" />
<EventRecordID>4215</EventRecordID>
<Correlation />
<Execution ProcessID="3728" ThreadID="10988" />
<Channel>Microsoft-Windows-WMI-Activity/Operational</Channel>
<Computer>DESKTOP-ORHEPT8</Computer>
<Security UserID="S-1-5-18" />
</System>
<UserData>
<Operation_ClientFailure xmlns="http://manifests.microsoft.com/win/2006/windows/WMI">
<Id>{00000000-0000-0000-0000-000000000000}</Id>
<ClientMachine>DESKTOP-ORHEPT8</ClientMachine>
<User>DESKTOP-ORHEPT8\mixvar</User>
<ClientProcessId>10480</ClientProcessId>
<Component>Unknown</Component>
<Operation>Start IWbemServices::ExecQuery - root\cimv2 : SELECT * FROM Win32_PerfFormattedData_Tcpip_NetworkInterface</Operation>
<ResultCode>0x80041017</ResultCode>
<PossibleCause>Unknown</PossibleCause>
</Operation_ClientFailure>
</UserData>
</Event>
ClientProcessId points to Speccy.
