The AWA score is computed in multiples of 0.5 and the maximum score is 6.0 points. All top ranked b-schools take the AWA score very seriously, and anything below 5.0 will affect your application negatively. Aim for a 6.0 or at least a 5.5 on AWA
As far as score in the IR section is concerned, b-schools that look at this score seriously expect to see a 5+ score in this section.