Hi David, Jordan, On Sun, 15 Apr 2007 16:03:09 -0600, David Hubbard wrote: > Hi Jordan, > > On 4/15/07, Jordan <xero at xeron.cc> wrote: > > I have a MSI 975x Platinum, which uses the w83627dhg. This one here: > > > > http://www.msicomputer.com/product/p_spec.asp?model=975X_Platinum_(Limited_Edition)&class=mb > > > > I've applied the DHG patch to my kernel (2.6.20) but I'm currently having some > > issues controlling the fan speeds. I've tried pwmconfig as well as manually > > echoing some values to pwm1-4 and pwm1-4_enable. It does correctly control > > my case fans, but it doesn't seem to have any effect over my CPU fan. I am > > using one of the new 4 pin cpu fans. > > > > My bios has a "smart fan" option for the CPU fan which does work correctly, > > although this option is not very configurable in the BIOS, it's only an > > on/off switch with no way to control the temperature that it raises the fan > > speed at. I found an actual picture of the BIOS screen for reference: > > http://www.hardocp.com/images/articles/1168231380Rzv7IS7G0U_2_15_l.gif > > > > I was hoping to be able to control the CPU fan speed through lm_sensors instead. > > Disabling the smart fan in the bios leaves the fan running at full speed, but > > this doesn't seem to make a difference, pwm1-4 continue to have no effect on > > the fan speed. Any ideas? > > Unfortunately, it looks like your CPU fan really is just an on/off > switch. It may not be controllable by the w83627dhg chip. As you said, > you have manipulated pwm1-4 to no effect. If you can find a schematic > for your motherboard, I can tell you for sure. (Jan van Tiggelen, here > http://lists.lm-sensors.org/pipermail/lm-sensors/2007-March/019282.html, > seems to have access to some of them.) But the 4-pin fan design does > allow the fan to be controlled in this binary fashion, either on (full > speed) or off (low speed, or completely off) -- so I don't think there > really is any chance of actually controlling the speed of that fan out > port. I don't think that Jordan's CPU fan goes off. My understanding is that what Jordan qualifies as "on/off" is the BIOS option (no way to set temperature limits), not the fan behavior when the option is enabled. I don't understand why the manual mode doesn't work either, but the following things could probably be tried: * Jordan, you say you tried manual mode when the option was disabled in your BIOS. Can you try again when the option is enabled? If the BIOS does extra initialization when the option is on, it might make a difference. * You could try to dump the registers of the W83627DHG chip with the BIOS option off, and then again with the option on, and see if there are relevant differences. Make sure you do NOT let the w83627ehf driver load, though, as it could overwrite a few settings. Assuming that your chip is at the standard address (0x295) you can dump its contents with: isadump 0x295 0x295 If it lives at a difference address, adjust the command. * You could try leaving the option enabled in the BIOS, so the fan is in automatic mode, then check the value of all pwmN_enable files. If one has value >= 2, that should be the PWM output controlling your CPU fan. Then you can check the value of pwmN_target, and maybe change it to adjust the behavior. I seem to remember that the W83627DHG supports more fan control modes than the w83627ehf driver handles. -- Jean Delvare
