I just finished building a new gaming PC using the M4A89TD mobo w/ a 955BE CPU. I used the Scythe Mugen II HSF instead of the stock cooler, and I'm seeing some issues.
Initially, I booted the machine, and got a sequence of beeps indicating a hardware failure, saw a CPU Fan failure message from the BIOS startup, and noted that the HSF did not spin. I quickly powered down the machine and double-checked all the cabling. Once I had secured everything, I applied power again, making sure to watch the HSF. It started spinning for about a second or two, and then stopped. Once again, I quickly powered down the machine.
I then switched the connections for the CPU fan, which had a 4-pin connector on the board, and the PWR fan (which I was using for a case fan), which also had a 4-pin connector. This time, when I started the machine, the HSF was spinning, but the case fan connected to the CPU fan connector did not spin. I then went into the BIOS and changed one of the power settings for CPU fan from PWR to DC (it basically says to use PWR for 4-pin or DC for 3-pin). The case fan had a 3-pin connector, but the HSF had a 4-pin connector. I restarted again, and the case fan connected the CPU fan connector did spin this time. I powered down again, and switched back, and both fans now seem to work.
This has left me a bit concerned, however, as I now have the HSF with a 4 pin connector connected to the CPU fan connector, but with a BIOS setting that supports a 3-pin fan. It seems to be working, and the idle temp of the CPU is registering around 40 degrees C, which is a bit higher than I’ve read for a lot of people with this HSF but may not be that surprising since my cabling skills are…less than ideal.
Has anyone seen a similar problem to this? Is it expected that the Scythe HSF should be working as if it had a 3-pin connector? Does this sound like a problem with the mobo or the HSF? I’m leaning towards mobo, since I’ve been able to get the HSF to spin with a different power connector.
Why don't you connect the case fan to a molex connector like everyone else does?
If not connect it to a chassis fan header.
The Pwr fan header is not controllable and generally not used except for psu fans.
And the Scythe fan to the cpu fan header where it's ideally connected.