Antec P180b case fan connectors

I put together my new system last night and I found that the case fans (3 120mm tri-cool fans) can't plug into the chassis connectors on my motherboard (Asus P5B-Deluxe).

The case fan connectors have regular molex power connectors and so I had to connect them directly to my power supply.

I wanted to connect them to the motherboard so I could monitor their speeds in the BIOS. Aren't there other advantages of connecting them to the motherboard also?

It's not important.

Set your tricools to the low setting, and run TAT on your CPU and see how hot it gets. If it gets too hot, put the fans at medium and repeat.

Find a good balance between temperature and noise, then leave your fans at that speed. You shouldn't need to ever look at the fan speed, it's not a necessity, especially if you have lots of margin. Don't tune to a few degrees close, as CPU coolers gather dust over time and lose a bit of heat transfer efficiency.