Weirdness with the new power supply, what to do?

Question

Power Supply

I just got a PSU from Thermaltake. And everything seems to be working fine, but some nonsense happens when you click on "shut down" in Windows. The system correctly closes applications and exits, the screen goes blank, but the PSU and processor fans remain on (probably the rest too). At this time, it is not possible to turn on the computer back using the Power button, it ignores it. Tried to wait 5 minutes, continues to work. If you hold Power for a few seconds, the hard drive LED blinks once and all the equipment turns off completely, after that you can also turn on the computer completely normally.
Sobsno question - what kind of crap is this and how to deal with it? So far, there are two hypotheses - either this is a glitch, or some kind of intelligent system that tries to cool the components to the maximum before shutting down. In the second case, two reasonable questions arise - why during her work it is impossible to turn on the computer back, and how much time she needs to calm down - therefore, again, it looks more like a glitch.
A few words about iron.

• Power Supply - Thermaltake TR-500PCEU
  
• Motherboard - ASUS P5E3 PRO
  
• Video - ASUS Radeon HD 3650
  

The power of the PSU should be enough with a large margin - even when buying a couple of years ago, the vidyukha was not considered fancy, previously there was a 450-watt unit in the computer for a long time and felt great.

Answer 1

Thank you all for your help, I'll answer myself correctly :) Google and search on the asus forums helped. The fact is that along with the PSU, I installed a FireWire board in the system. The board is no longer new, and there were no such issues with it before - however, I didn’t try to use it under Win7 either, the previous motherboard had a built-in controller. In short, if 7ka does not set the default checkbox "Allow the computer to turn off this device to save power" in the "Power Management" tab in the device's properties in Task Manager. I checked the box - everything worked, even with ACPI turned off in the BIOS. Here is such a bullshit.

Answer 2

And what is Windows? Maybe he needs a driver for the PSU?

Answer 3

The very fact of the fans working after turning off is not a glitch, I have the same situation in hot weather, they turn off after 5 minutes.
But the fact that you can not turn it on in this state is already a glitch.
It's better to ask overclockers, I think.

Answer 4

Check if ACPI is enabled in BIOS

Answer 5

In principle, I agree with AnViar, if the power supply is working, then editing ACPI should help.
Alternatively, try resetting the CMOS, unplugging the PSU again, and plugging it back in. If it doesn’t help, try it on another computer, but if the same crap is there, change it under warranty.
PS: I have never encountered a situation where the PSU continues to work after being turned off, despite the fact that I live in a country with an average annual temperature of about 25 degrees.