Case Fans

I'm putting a new rig together. All the fan headers on the mobo are four pin. All the case fans are three pin. Is there a solution to hook them to the board (adapter?)? The fourth wire on the board headers are a tach readout I am guessing. A three wire fan is PWM I am guessing again. I don't really know. What do my fellow forum members do in a case such as this?

I wondered about that. What do I lose. Speed control or tach readout?

I am not familiar with these bios yet. I don't see (actually looking at manual) a PWM control. Although I am going to guess some of these settings is actually PWM.
for instance "***Q-Fan Control".

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Hello Bob,

When using a 3-pin power connector with a 4-pin fan header, the fan is always on; there is no fan control.

The link below can help show you how to connect a 4-pin fan on a 3-pin fan header. Be sure that the red wire is connected to pin 1. :)

Desktop Boards -- 3-pin and 4-pin fan connectors

Thanks Brink!

You're most welcome Bob. :)

Gosh Brink, I hate to argue with you, but, I will.

Many motherboards have fan control built-in to the BIOS settings these days, though they don't always give you as much control as something like SpeedFan does. But, if your computer isn't supported by SpeedFan, this is a good plan B. Open up your motherboard's BIOS settings (usually by holding a key like Delete when you boot your computer), and search for the fan settings. They're called all sorts of different things (for example, Asus has "Q-Fan Control", while Gigabyte has "Smart Fan Control"), but generally you should be able to find it under one of the BIOS menus. Enable this feature, and tweak any settings it gives you to your liking. Some machines may only let you set it to conservative or liberal mode, while others will let you individually set temperature thresholds like SpeedFan. It'll also offer you a choice between two regulation methods: voltage and PWM. The voltage mode adjusts the voltage of the fan, while PWM mode sends calculated voltage pulses to the fan to make it run a bit slower. For the most part, this depends on how your fans are plugged into the motherboard. Fans connected with a 4-pin connector should use PWM, while fans connected with a 3-pin connector should use voltage. Voltage is slightly less efficient, and you can't get speeds quite as low as with PWM, but PWM can be finicky sometimes too. If you find PWM is giving you problems, you can always switch to voltage. And, if you can't connect your fans to the headers on your motherboard (that is, if you're using the large, 4-pin Molex connectors), you'll need to use method 3 below. Again, your motherboard will only support this kind of fan control for a few fans, too (usually your CPU fan and a system fan). If you want to control them all, check out method three below.

Control Your Computer's Fan Speeds for Better Performance When You Need It, Silence When You Don't

I know this to be true, because I use this feature in my BIOS to control my 3pin fans.

I plugged the fans in to the board. I can't check them yet I don't have the CPU. Been waiting on Ivy Bridge. I have an Asus P8Z77-V Deluxe which supports fan control. Asus provides a bunch of bios setting which I posted earlier and the install disk has a fan control app. After reading your posted link I may have some control of them. I won't find out till I get a chip. (soon I hope) Thanks for the replys.