Fans Do Not Completely Shut Off On System Shut Down

[NJDeac]

1. Overview of the problem
   When I shut down my PC (select the shut down prompt in Vista from the expanded restart/shutdown/etc. menu), the fans and case lights do not shut down all the way.
   
   
2. Full description of the problem and symptoms
   This problem has been occurring since I put the PC together. As stated above, I select "Shut Down" from the dialogue menu in Vista, and Windows shuts down, as do most of the fans in the case. The two front case fans become much slower, but do not power down all the way. Furthermore, the CPU and power supply fans sometimes appear as if they're *trying* to start to spin, but move a tiny bit and then stop. This behavior is somewhat intermittent, with the PS and CPU fans often stopping completely. The internal case lights remain on.
   
   I've checked Windows Event Viewer and there seems to be nothing odd happening in the OS during shutdown. The problem disappears when I toggle the kill-switch on the back of the power supply, and everything stays shut off when I turn it back on - at least until I boot up and give the shutdown command again.
   
   Also worth noting - holding the power button in for 5-10 seconds to force a shutdown causes the same symptoms. The system is NOT in a state where it's trying to shut down and failed, because pressing the power button again causes it to restart. It is as if it thinks it is powered all the way down, but a tiny bit of current is still flowing to the fans.
   
   
3. Did it work normally at one time, or has the problem always existed?
   No, it has done this since I put the machine together a couple of months ago, and seems to be more annoying than a major problem. Still, I'm worried it might be indicative of some other problem.
   
   
   
4. Is the problem consistent and repeatable, or entirely random, or semi-random?
   Happens every time I shut down.
   
   
   
5. I already tried these steps:
   I've tried updating the BIOS on my mainboard, to no effect. I've also disconnected all non-essential peripherals and it still occurs.
   
   
   
6. My software:
   • Windows Vista SP1 32bit
     
   
   
   
7. My hardware
   • Asus Rampage Formula Mainboard (Latest BIOS)
   • Intel Quad Core Q6600 - Not currently OC'd
   • EVGA GeForce 9800 GTX - Not currently OC'd
   • 4x1GB Crucial Ballistix - Not currently OC'd, default voltage
   • HIPER HPU-5B680 680W Power Supply
   • Antec Nine-Hundred Case
   
   
8. Other information that might be relevant
   N/A
   

[/quote]

 

[robisbell]

what is the power management set up as in the BIOS?

 

[NJDeac]

Originally posted by: robisbell
what is the power management set up as in the BIOS?

By default, "Suspend Mode" is set to "Auto", "ACPI 2.0" is set to "disabled", and "ACPI APIC Support" is set to "enabled".

I tried enabling ACPI 2.0. I was able to boot windows fine and then shut down, but the problem continued.

I then tried disabling both ACPI 2.0 and APIC, and was unable to boot windows. It hung shortly after the POST and RAID controllers doing their thing, and when I restarted and reenabled the power options, it gave me a "Windows failed to start normally, do you wish to start in safe mode?" prompt, and then started normally.

I didn't change the Suspend Mode settings, since it talked about some S1 and S3 options which I wasn't sure what they did.

Thanks for the assistance, this give you any ideas?