Did I cripple my mobo?

This is a new build for me. I have an Asus P8z68v-pro gen3 mobo and was attempting to connect 1 of three case fans to the mobo (the other two are connected to the PSU and work fine). I connected the molex to a 4 pin adapter so i could plug it into the mobo. The mobo did not like this fan being plugged into it. Once plugged in, I started the computer and the mobo would not work. The fans wouldn't spin either. I tried this 3 times and on the third time there was a puff of smoke and a flash on the mobo near the cha-1 pins where I had connected the fan. I quickly shut down the computer and disconnected the fan. There is a small circuit near the cha-1 pin that looks to be burned, but the computer starts up just fine and I'm able to play games/surf the net etc. I've been monitoring the gpu & cpu and both are doing fine and working as they should. Everything seems to be working including my other two case fans as well as the cpu fan....just can't get the third to work and I'm incredibly concerned about the mobo after this. My question...do I need to replace the mobo even though everything seems to be working fine? Any idea what would have caused the burn on the mobo? I'm thinking of getting a molex adaptor to plug the 3rd fan directly into the psu...is this dangerous?

The PSU is a brand new corsair TX650w Mod 80+.

Thanks for your thoughts guys...