What is the crowd's opinion of
Argus Monitor?
From 3.5 billion comments
2 reviews of this app found across the web:
Seconding Argus Monitor. The BIOS in my motherboard had a fan control bug, only way I managed to get the fans to run at a sane speed was Argus. Well worth the ~$20USD. Very easy to configure, and just works. 30 day trial to test with.
So... a couple suggestions. First, as I initially mentioned, if you have a way to monitor the CPU speed over time (like Argus Monitor) you should fire that up, then launch overwatch and see if your CPU speed ever drops. If it does, then thermal throttling is to blame. If it doesn't, then something else may be going on.
Regardless though, you should still bring your CPU temperatures down. I'd suggest going into the BIOS to see what the voltage is set to right now, then switching from AUTO to manual control and dialing back the voltage in 0.05 volt increments until the system becomes unstable. Although a bit of an apples-and-oranges comparison, I'm running my i7-6700K at 0.25v under the voltage that "auto" set it to and it's: a) rock-solid stable and b) a heck of a lot cooler than it was at "auto".