Computer was working fine. Now mem ok light is on and fans have stopped working.

[GMonah]

So heres my deal. Put together my first computer with the help of you guys. Nows its 5 months down the road. I'm using my computer when all of a sudden the screen goes black and both my keyboard and mouse lights (power) turn off, almost like the system is shutting down. I look over at my computer and the fan's and everything are still working except i see a red light on now (turns out to be mem ok light). I go to turn my comp off with the power button but it doesnt work so i eventually end up turning off my power supply. So now i turn my system back on and the rear and cpu fans are now not working. The fan for my gpu is working and the front case fan is also still working. Pushed the mem ok button and now it is flashing red. I just have no clue where to start. Any help would be much appreciated.

My specs:
Cpu : Amd 8320fx
Motherboard: M5a99fx pro 2.0
Power supply : Corsair cx750
Graphics Card: Asus Geforce GTX 770

Also on a side note my friend gave me an extra copy of windows but forgot to give me the activation code and i am well past the activation date (i get all the activation messages). The only reason i mention this is to see if it might have anything to do with my problem. And also is it safe to even leave my comp on if the fans aren't running (will it overheat?) Thanks again guys.

 

[Videographer]

Sounds like a faulty motherboard or a power surge. Try the front fan plugged in to the other sockets to determine if your fans are broken or the motherboard is broken. And stop using pirated windows as a side note because only Microsoft has the activation codes