The real question is do you have the cooling to take care of the processor as you overclock it. That is what will determine if its stable along with your MOBO and other specs. the PSU should not matter, but after closer examination of your PSU, it only have 2 12v rails at 18 amps each. total of around 35 amps, the card alone pulls up to 25 amps, that leaves the 10 amp overhead in torture testing for your CPU and other 12v draws.
Your CPU overclocked is pulling max like 8-9 amps, I have also been rounding so in the end you will have around 5-10 amps on your 12v rail remaining and you can easily use a small amount of this to OC. but if you are not changing voltage and only frequencies, then it wont pull more power then its allocated, this is when over clocking truly comes into play, then you need to up the voltage in order to support higher frequencies.
But most importantly you want to make sure you have a CPU cooler that can handle it, Like your current one if you attached another fan for a push/pull config and set it up correctly you can prob have a good overclocking time.
Im not sure if that MOBO is good for overclocking, when overclocking you usually have to have a mobo as well thats ready for the OC.