That S5 was running in the low 60's at 3960 RPM - After the thermal compound it dropped to 50 at 3240 with the same room temperature.  Lower HW errors too.  I'll pull the next worst one tonight and repaste it for comparison.   The Gelid stuff is really stiff and gluey compared to the Arctic Silver compound.   That's probably a good thing   If I were completely ADHD I'd sort the boards across units and get matched sets lol.