Hey all! I've posted this issue in the LTT forums, but couldn't get any help, so I figured I'd see if you could help. At the moment, whenever I boot my PC, the case fans won't spin up. I have to manually spin or blow on them to get them started, and after that, they're good. I'm assuming that this is a software issue, and that my PC simply isn't starting the fans at full speed (followed by slowing them down, like it does for my CPU fan), and is instead trying to start them at half speed. Does anybody know of any software that I could use or settings I could change to get the fans to spin at full speed on boot? I tried the BIOS, but there's no option for changing the fan startup voltage. I'm currently using the ASUS Fan Xpert software to control my fans. Thanks for your help!
Sounds like you hit the problem on the head, If the fan voltage is too low they will not be able to start up (motors take more energy to start initially). Just to be check everything that could be wrong have you tried not using Mobo headers for the fans? If they are still acting up the fans could be defective. Also I wouldn't think this is the issue, but, you are not by chance using voltage regulators on the fans, right? Software likely isn't messing with your voltages at start-up (some software does, turn off stuff like Corsair Link, and set Fan Xpert to defaults), its more likely either the board is bad or the BIOS is set up incorrectly. For Asus I think you can change the fan profiles in the BIOS try setting them to performance mode maybe that will fix it. Worst case, the Mobo itself isn't regulating voltage correctly; if that turns out to be the case I would start a RMA process.
As an extra note try and see if you can find out the fan RPMs for the case fans you are using if you set them too 100% in software and they are not getting close to the rated RPM then you know right there that the voltage delivery is not working. IE defective fans/Mobo.
If you just want to try and use software to band-aid it try Speed fan
http://download.cnet.com/SpeedFan/3000-2094_4-10067444.html
I don't use it personally but I have heard good things.
The mb supplies 12v and you have these setting maxed? Have you tried to hook the fans up to molex straight from the psu? At least to see if they start up normally. If so you could get another type of fan controller if you want to tune the down.
What type of fans are they and the specs
No voltage regulators on the fans, and they startup fine when set on 100% power. I'm just going to wait until I upgrade my mobo, because apparently ASUS really likes to change the fan options from board to board - and seeing how mine is old, it makes sense that the option isn't there. I'll just stick with making sure to set the fans to 100% right before shutting off.