What is the maximum psu i can use with my motherboard

Hi ronkwas and welcome to Tom's hardware forum.

You can use any PSU, but that depends of the power that you need. You mobo will not be hurt by the PSU (unless for a short or something like that), but doesn't have sense buy a 1200W or 1500W PSU if you only will use 400W or 500W.

I don't think your limited on the psu you can use, the board will only draw the power it needs.

But as the saint says no point fitting a 3 litre engine in a mini metro.  

yeah like everyone else said you can get as high a wattage psu as you want.