I recently upgraded to a 3700x and am having confusion when monitoring temperatures. I'm currently using a wraith spire stock cooler (the middle option of amd stock coolers) for cooling which isn't the ideal but is rated for 95 watts. The programs I've been using are MSI Afterburner, HWINFO, and Ryzen Master. MSI Afterburner seems to be reporting the highest temperatures with idles within the 50-65c on idle but with random jumps in temperatures (i.e. going up from low 50s to mid 60s and then back down). HWINFO reports 3 separate temperatures "CPU", "CPU Die", and "CPU CCD1". Temps for the first ranges from 50-65c on idle but also has random jumps (i.e. going from 51 to 57 and back to 51). Temps for the other two tend to be lower ranging from 40-50c on idle with less sudden dips and rises. Ryzen master reports the lowest temperatures on average with low 40s to mid 40s on idle. Under heavy load, temperatures throughout all programs reach around the same temperature (70-80c) with MSI Afterburner reporting an max of 83c. Overall, why do these numbers vary so much and is there anything I should be concerned about?
Those are 3 different sensors within processor.
CPU = Highest core temp, hottest core.
Ryzen doesn't report temps of each core individually but use that temp to decide on maximum boost for that core.
CPU DIE = also used to be called "Socket temperature" as sensor used to be placed at bottom of socket on MB but with modern PC it's moved to CPU itself. Includes temps of all CPU components including memory and other controllers (like eventual IGPU), IOs like PCIe controller etc.
CPU CCD1 = Ryzen is made in segments (chiplets) one of which is memory and IO controller and CCD is chip(let) containing cores. 12 and 26 core Ryzen use 2 of those, 8 core only one therefore CCD1. R9 5900 and 5950 have two of those so it would show as CCD1 and CCD2. Also shows temp of hottest core in each.
Ryzen Master shows "Effective temperature" as temperature used to determine amount of boost at auto boost/PBO settings and which cores can be loaded most, it can automatically switch load to another, cooler core if one gets too hot (about 70c on 3000 series Ryzen).
For general purpose, use Ryzen Master as reference as it's most useful, for details, HWinfo is most accurate.
PS:
Temps jumping up and down is normal as it reflects load (and voltages) at any given time. All OSs including windows keep on doing things in background even at apparent idle so temperatures variations occur too.