dell 5160 mother boards, Internet

been having issues with power supplys and mother boards for the 5160 inspiron,
since the warranty has expired they want me to pay for everything that is going on,thank god for the internet and eBay,
Ive had the power supply go bad 2 times, the CPU started acting up and when i disconnected it i found they never used the heat transfer grease. after i put it on it worked good.Ive replaced the hard drive,now i get a amber light which i can't get any answers on because they want money for their  defective device,i think i have to replace my mother board.its been an on going struggle,i don't think i will go back for another dell