First time building a PC and fans dont work, help.

I need some help troubleshooting the new PC I've built. Everything is working except for my fans.

I have a CPU Cooler master, built in mb fan, and 2 others fans that all use the 3 pin header connection to the motherboard for power. However, when I turn the PC on none of them seem to work/power on. I am using a Asus A7v 133 Socket A motherboard.

Does anyone know what I can do to get the fans working? Could it be the motherboard? Obviously I don't like keeping the machine on (even though it works) because things get hot real fast. But I was able to check everything else and it all works just fine.

Other info if needed to help (all working):
I have a 750 Duron processor
Win 2k Advanced Server OS installed and working
30g Wdigital HD
Floppy
52x CD Rom
TNT 32GB video
3COM NIC
300 W Power supply

Finally, I've called Asus and they believe the mb might be bad, but I'd like to troublshoot everything before I take it back since I know it will take forever to get back or replaced. And in case it's not the mb after all.

Please email me at maddux@houston.rr.com if you can help.

Thanks in advance!

Mike