What part do I need to buy to fix this?

My phone got wet. It is dry now It will not boot up, but it only has a fuzzy looking lit screen that is sometimes, green, red, orange, yellowish looking. It has lots of speckles in the screen. Sometimes it is black with colored speckles in it. I never see the galaxy intro, just the fuzzy lit screen, but only temporarily. Can it be fixed and what part would I need to purchase? I already have lots of spare parts and would like to fix this one. Does it need a new mother board? I tried all the suggestions of hold down the power button while pressing the volume down button, then power with volume up, then power volume and home. It still does not boot or work. Watched all the youtube videos I could find, but nothing matches this problem. Saw the red screen of death at one point, but colors change.