I am generally reluctant to involve a newly-arrived Ph.D. student who
is taking a full courseload in my research projects, until after the
student has been at Purdue for at least one semester.  I actually
prefer to wait until the student has already passed all the Qual I
requirements (although a student who, for example, took and passed 3
quals in their first semester, may impress me enough to make an
exception).  I will generally not provide RA support when the research
interaction is just beginning -- I will wait for evidence that we can
work together and obtain research results at a level and rate in line
with what I expect from my Ph.D. students.