//preload common images
if (document.images) {

	var photos_on = new Image();
		photos_on.src="images/nav_photos_on.gif";
	var photos_off = new Image();
		photos_off.src="images/nav_photos_off.gif";

	var videos_on = new Image();
		videos_on.src="images/nav_videos_on.gif";
	var videos_off = new Image();
		videos_off.src="images/nav_videos_off.gif";

	var games_on = new Image();
		games_on.src="images/nav_games_on.gif";
	var games_off = new Image();
		games_off.src="images/nav_games_off.gif";

	var performance_on = new Image();
		performance_on.src="images/nav_performance_on.gif";
	var performance_off = new Image();
		performance_off.src="images/nav_performance_off.gif";
		
	var what_gpu_on = new Image();
		what_gpu_on.src="images/what_gpu_on.gif";
	var what_gpu_off = new Image();
		what_gpu_off.src="images/what_gpu_off.gif";

	var what_mcp_on = new Image();
		what_mcp_on.src="images/what_mcp_on.gif";
	var what_mcp_off = new Image();
		what_mcp_off.src="images/what_mcp_off.gif";

	var choose_gpu_on = new Image();
		choose_gpu_on.src="images/choose_gpu_on.gif";
	var choose_gpu_off = new Image();
		choose_gpu_off.src="images/choose_gpu_off.gif";

	var choose_mcp_on = new Image();
		choose_mcp_on.src="images/choose_mcp_on.gif";
	var choose_mcp_off = new Image();
		choose_mcp_off.src="images/choose_mcp_off.gif";
	
	var tab_gpu_front = new Image();
		tab_gpu_front.src="images/tab_gpu_front.gif";
	var tab_gpu_behind = new Image();
		tab_gpu_behind.src="images/tab_gpu_behind.gif";
		
	var tab_mcp_front = new Image();
		tab_mcp_front.src="images/tab_mcp_front.gif";
	var tab_mcp_behind = new Image();
		tab_mcp_behind.src="images/tab_mcp_behind.gif";

}

//mouse over/out functions
function navOn(foo) {
	document.images[foo].src = eval(foo + "_on.src");
}
function navOff(foo) {
	document.images[foo].src = eval(foo + "_off.src");
}

function showGPU(foo) {
	document.images["tab_gpu"].src = eval("tab_gpu_front.src");
	document.images["tab_mcp"].src = eval("tab_mcp_behind.src");
	document.images["title"].src = eval("gpu_" + foo + "_title.src");
	document.images["main"].src = eval("gpu_" + foo + "_main.src");
}

function showMCP(foo) {
	document.images["tab_gpu"].src = eval("tab_gpu_behind.src");
	document.images["tab_mcp"].src = eval("tab_mcp_front.src");
	document.images["title"].src = eval("mcp_" + foo + "_title.src");
	document.images["main"].src = eval("mcp_" + foo + "_main.src");
}

//set the image map for the main image
function setMap(foo) {
		document.images["main"].useMap = "#" + foo;
}