T60 dead audio chip

[DELLmanCze]

Hello

When i turn it on, LEDs are on, fan start for 5sec, then it stops... after two minutes it starts again at max speed and then power LED turn off... i disassembled it and started "naked" (only Mainboard, with LCD attached) and checked temperatures on all chips, the AD1981HD is very hot in few seconds. Can i try something cheaper than new MoBo ?

Thanks