Info on SpeedFan

halfpower · Post by **halfpower** » Thu Sep 29, 2005 4:19 am

There is an option in SpeedFan that says "set fans to 100% on program exit." Can anyone explain to me how my computer manages to hold the fan settings after the program has closed out?

Bluefront · Post by **Bluefront** » Thu Sep 29, 2005 4:31 am

Well can speedfan control your fanspeed at all? If it cannot, it will not be able to speedup your fans when you close the speedfan program.

This is a sort-of safety device....should any program crashing occur, your fans go to 100%. Works for me, but only on those computers that speedfan can control. On the other computers, speedfan only reads temps, but cannot control fans.

Aleksi · Post by **Aleksi** » Thu Sep 29, 2005 4:32 am

Hi,

they only stay at 100% if another piece of code (BIOS or fan control software) doesn't set them to another value. So if you have enabled in your BIOS the automatic fan speed control for i.e. your CPU fan, when exiting Speedfan it sets the fan output to 100% but it is shortly brought down by the enabled BIOS control.

But if you don't have any options enabled in BIOS (for fan controlling) then the fans will stay at 100% until a different value is written to the control register.

So you don't have to tell your fans constantly to run at a certain speed, the chip controlling the fans just checks certain register values to see how fast it should run the fans. So if it is set 100% it will stay at that "automatically" without PC software.

Hope you got the idea, my explanation might be a bit confusing?

halfpower · Post by **halfpower** » Thu Sep 29, 2005 4:35 am

Will it go back to 100% when I reboot?

Aleksi · Post by **Aleksi** » Thu Sep 29, 2005 4:40 am

If you don't have any BIOS fan control enabled, then it will most likely go to 100%. I think it's a sort of a default on most motherboards. Like when you start your computer, the fans should be running full speed.

Bluefront · Post by **Bluefront** » Thu Sep 29, 2005 4:41 am

Actually if you restart speedfan, the fan control goes back to normal. Rebooting also returns everything to normal.

Some computers have a fan-control system that conflicts with Speedfan...in those cases anything can happen.

To fix such behaviour, disable the fan control in one or the other...

JBDan · Post by **JBDan** » Thu Sep 29, 2005 10:54 am

halfpower wrote:There is an option in SpeedFan that says "set fans to 100% on program exit." Can anyone explain to me how my computer manages to hold the fan settings after the program has closed out?

I cannot explain it, but a soft reboot without the "set fans to 100% on pgrm exit" box checked will leave your fans at the user set speed. Even if I close out the program, my fans remain at my specified speed. I would think that this is a registry entry that allows your fans to remain at your specified speed even when the prgm is shut down. However, if i turn my pc off (hard reboot), then when I power back on, the fans are at 100% until SF loads if its in your startup folder. I leave it unchecked because I see no need for them to ramp up to 100% on exit. This is my case anyway.

StarfishChris · Post by **StarfishChris** » Thu Sep 29, 2005 2:28 pm

The fan control chips are initialised to run at 100% when the PC is turned on. If you have no BIOS fan control enabled (or you disabled it in SpeedFan advanced settings) the fan speed won't change after a reboot.

halfpower · Post by **halfpower** » Sun Oct 02, 2005 1:20 pm

Okay, I just unchecked "set fans to 100% when program closes," rebooted, and started Linux. My fans stayed at 53%! I'll think I'll have to test this with a cold boot.

Info on SpeedFan

Info on SpeedFan

Re: Info on SpeedFan