Started getting this error:

PERFMON:CPU Idle Time in % is low

Where would I look to get information on what is throwing this error and how to resolve it?

S7 Engineering Station

Hello DeanFerguson,

the message means that the CPU-load of your PC station is high. So you can have a look in the Windows task manager to get information. 

Under the FAQ "How can you recognize resource bottlenecks in advance from WinCC and react to them accordingly?" you can also find some information:
https://support.industry.siemens.com/cs/de/en/view/954032

To find out which process cause the high CPU-load you can use the windows performance monitor.
How to use the Windows Performance Monitor is described under the FAQ "How do you perform comprehensive diagnostics in PCS 7 and WinCC plants?"
https://support.industry.siemens.com/cs/de/en/view/48698507