An apparatus includes a heat generating component; a heat radiating member
that absorbs heat from the heat generating component and radiates heat; a
fan that sends air toward the heat radiating member; a housing
incorporating the heat generating component, the heat radiating member
and the fan, and including a first opening that discharges air warmed up
by the heat radiating member to an outside and a second opening that
exposes an air inlet portion of the heat radiating member in which air
from the fan enters; and a cover member that is detachably attached to
the housing and covers the second opening.