The claimed safe limit* for a Phenom II is 62°C, but the monitoring tools aren't always fed correct data because the internal sensors aren't precise enough. Your reading can be 7-10°C off in any direction. AMD has built-in safety feature that shuts the CPU down once it hits 90°C, as real degradation apparently only begins at 92°C.
So you do have a temperature problem indeed. However I don't think your CPU cooler is to blame here ... unless it is incorrectly installed.
You mention that the entire top end of the case feels red-hot, which sounds to me like lack of airflow. Then again the CM 690 II is a good case, so I'm wondering what's going on. I could understand it if you were running some super-hot GFX card, but a GTX570 doesn't generate enough heat to cause any problems in your case.
Check every fan's direction by holding your hand in front of it. The front and left-side fans should be sucking the air in, the other fans should be blowing it out. If necessary, open the case and put a desk fan next to it.
If it remains stable that way, you'll need to upgrade your case fans or get a better case.
I had a similar problem, and found out that my 4870X2 was blocking airflow in my old Gigabyte iSolo 210 case and creating too much heat as well. I moved up to a CM HAF X and my problems vanished even with the case fans set to half their normal speed.
* the maximum temperature it is allowed to maintain over a long period of time