Temperature Difference Between 2 CPUs

[HilltopsWS]

I recently purchased a used H6 Z4 Workstation with two Xeon God 6138 CPUs. The second CPU has a CPU Riser Board Heatsink.
I noticed that the temperature of the first one varies between 104 and 113 while the second one shows much higher temperatures, between 115 and 138 (with the fan occasionally being heard) . These temperatures are measured with regular loads of a number of open Chrome pages and a few apps. All at idle, so not really processing anything.
I wonder if there should be such a difference between temperatures, on average ranging between 18- and 27-degrees F (10 to 15 degrees C). Should I go back to the shop that sold me this machine or is there something I can do myself?

[HilltopsWS]

So many people viewed the post but no reply. I understand that my machine is no longer under warranty but I had hoped to get some information to better understand what might be wrong with the temperature differences between the two CPUs and what could or should be done about it. So, please....