What is this hole on the bottom next to the part where you put the ram? It is on the speakers thing i think. Looks like the led that goes red like it does on macbooks? Using the first gen imac maybe, 1.83 ghz, 512mb ram, 160gb hd. And how do you remove the residue on the stand thing where they put that plastic sticky tape on it? It was covering the hole so I removed it.