I've installed this program a few times over the years, and I almost always immediately uninstall it. This time I reinstalled it because I was considering a case fan that would be nice to have if I could control the speed profile (it might be very loud if ran at full tilt). The BIOS has an extremely basic control for throttling the fans - basically, below a set temp, it idles at the speed you pick, then above that temp the system slowly ramps up the fan speed until the temperature is back on target or the fan is at max speed. I remember AXTU having some kind of control over this, and it's received a few updates since I last tried it, so I installed it again to see if it was any different.
Not only is there no reason to install it (the controls are EXACTLY the same that the BIOS offers, just presented a little differently), and not only did it hang my system (I expected it to - the reason why it doesn't live here for very long), but this time it actually rendered my system unbootable! And I didn't even alter a single setting in AXTU! "Dr. Debug" kept showing code 32, which apparently is a non-specific memory error, but clearing the CMOS got it to boot again.
Now, this won't happen to everyone. It probably doesn't even happen to most - I'm using an Asrock Z68 Extreme4 Gen3 (still kicking) and it clearly does not get along with it, but I see reports elsewhere of people being happy with it. If it fails like it did for me, you'll know pretty quickly - if it's working for you now, this will probably never happen to you.
IDK, I had to rant about it somewhere, this seemed like the best place to do it. Pretty cheesed about it - since AXTU has voltage controls, I was worried for a few heartstopping moments that it had actually blown something.