Originally Posted by Italianguy
I have a few questions about fan configuration. The z77-v deluxe board has 6 fan ports: CPU_FAN, CHA_FAN1-4, and CPU_OPT.
Do I have the following things correct about them?
- CPU_OPT can not be speed controlled.
- CHA_FAN1-4 can speed control 3 and 4 pin fans.
- Can CPU_FAN control the speed for 3 pin fans? Or is it only 4 pin fans?
I noticed it says this in the manual, "The CPU_FAN connector supports the CPU fan of maximum 1A (12W) fan power." Now it doesn't mention the other fan ports, does anyone know what those are rated for?
My setup is going to be the following. Computer Chassis, Obsidian 650D (The following fans are not the stock case fans):
- Top: Two 140mm 3 pin fans.
- Front: One 200mm 3 pin fan, one 120mm 3 pin fan.
- Rear: Antec KUHLER H2O 920, push/pull configuration: Two 120mm 4 pin fans.
The Antec H2O 920 has one 3 pin plug that powers the one pump and the two 4 pin fans (The 4 pin fans are controlled via USB connection through software). I've read that its probably NOT a good idea to have all 3 of those powered off the motherboard for two reasons: because of the power it'll consume on one fan port and because if the motherboard tried to lower the RPM speed it could damage the pump.
Because of those reasons I figure its best to directly connect the Antec H20 920 to the PSU, having the software through USB control its two 120mm 4 pin cpu fans. Do you guys think this is the best option? I asked in the begining of my post if the CPU_FAN plug can speed control 3 pin fans. Because if it CANT then, theoretically, I could plug the pump into the CPU_FAN (without having to worry about speed changing) assuming the port could handle the pump and 2 fans. I'm not so sure the CPU_FAN rated at 1A, 12W is enough to do that.
So assuming I didn't do that and did just plug the Antec H2O 920 into the PSU, I have another problem. That leaves me with only four chassis 3 pin fans. Now I'd want to plug those into the CHA_FAN1-4 so that they can be speed controlled. That would mean I have nothing plugged into CPU_FAN. I've heard that if you don't have something plugged into CPU_FAN, you're going to get an error about there being no CPU fan. If it turns out CPU_FAN can speed control 3 pin fans, then I can just plug one of the chassis fans into there and be done with it. Unfortunately I don't have my parts yet to test this out, and from what I see the manual doesn't say specifically if it can control 3 pin fans.
So what do you guys think? What would be the best configuration for my planned fan setup?
I can hopefully answer this as I had similar questions (and now own the P8Z77-V Pro which has the same fan setup).
1) CPU/CPU_OPT are controlled via the same circuit, so settings applied to one apply to the other.
2) CPU/CPU_OPT can only control PWM (4-pin) fans, if you plug in 3-pin it runs at full speed, no voltage control available (I've tested this, and confirmed by Asus)
3) CHA1_4 can indeed control with 3-pin (voltage) or 4-pin (PWM), and you can mix/match 3/4-pin on various headers, I have done this successfully
4) For your 920 setup, I'm not sure what is optimal, you can use a 3-pin for the pump since it will not change the speed (but will report the RPM). You can disable the CPU Fan warning in the BIOS I believe if you are concerned about that.
5) You can use 3-pin splitters if you want, to share two fans on one header, as long as the fans are the same. 99% sure this works, haven't tested it yet, but both fans would receive the same voltage and thus run at the same speed (if they are identical models).
Corsair 550D (3x stock 120mm fans, two in front, one in rear + 1x 120mm PWM fan in bottom)
Noctua NH-D14 heatsink with 2x 3-pin fans
I have the 2x 3-pin fans into CPU/CPU_OPT and the 4x case fans in the other 4 MB headers. I can't control the CPU fans so they run at 1200rpm, I'm planning on using a 3-pin splitter and running both CPU fans into a chasis header, then using another splitter to run the two intake fans off another header, thus I will be able to control all fans using Fan Xpert 2 (AI Suite within Windows). The fan control options are awesome on this board, the only downside is you can only use CPU temperature (read by the MB) for the fan curves, on the Sabertooth you can use different temperature sensors (and average them etc).Edited by grambo - 5/15/12 at 1:41pm