wattage is ok as u r above the required...usually it is recommended to use atleast a tier 2 psu for better longevity but risks involved is purely based on luck...a lot of ppl do OC and work fine, while a lot other have experienced their pcbs fry out with bad quality psu...for eg, if a tier 1 psu has 5% chance of anomaly then a tier 3 can have somewhere around 20% to 25% chance of playing up...u can do the rest of the maths...