I Need Some Help!!!

i need some help
i need to cut a blow-hole in the top of my aluminum case, but how do i do this???? The holes need to be round!

Well frist measure out were you want the fan hole and the center of the hole.You can either use a dremel tool or a drill or even tin snipsa.Personally i would go to Lowes and buy a nice dremel tool kit or get a drill bit thats made for cutting holes.Im pretty sure they have them for metal.But the easy is just use the dremel tool to cut it out.And then grind down the ruff edges with the dremel tool.Or you could just drill a whole bunch of smaller holes inside the circle you plan to cut out

what bit for the dremal do i use?

The cutting wheel.Im not sure if they have any thing better for cutting.But i would use the cutting wheel.I