Fran sorry to burst your bubble but you should know that all this latest hardware is NOT going to make Silent Hunter III look as good as Silent Hunter 5. Sorry...
Though I'm curious why the kickass PC, what other games do you play beside SH or are you looking at getting into 3dstudio max or something. Anyways the higher the hw the better 750watt sounds right, Radeon HD 5770 (wow!) Im running a pesky 9800GT works fine for all latest games so far. 2 HD 5770 will cream everything thrown at it imo.