of chip 24 to pedestal 46 the degree to which pedestal 46 is biased towards chip 24 may vary depending on the requirements and characteristics of chip 24 and heat sink 42 maintaining pressure at the interface between pedestal 46 and chip 24 also keeps heat sink 42 in thermal contact with chip 24 during moving and vibration thereof this arrangement also maintains generally even pressure at the interface between pedestal 46 and chip 24 plate 50 is preferably made from a metal but it may be made from any of a number of appropriate materials for example it may be made from steel beryllium copper aluminum e g 2024 or 7075 or some other metal or composite having a high modulus elasticity and high yield strength as discussed above heat sink assembly 40 is adaptable to many different configurations of substrate assembly 22 and different air flow pathways by rotating heat sink 42 relative to mounting plate 50 to obtain an advantageous orientation of mounting plate 50 and heat sink 42 referring to fig3 a to 3 d an embodiment of the heat sink assembly is shown generally as 62 heat sink assembly 62 is similar to heat sink assembly 40 and functions in a similar manner except as indicated below heat sink assembly 62 includes a heat sink 64 having fins 66 fins 66 are arranged in a generally circular oblong arrangement having spaces therebetween fins 66 are.