Linux On My Samsung

Just want to ask if there is a limit to the hard drive capacity that can be installed to an n140? I read somewhere that it is only 250gb or maybe I misunderstood that. Anyone ever try 320gb WD Scorpio Blue (IDE) on their samsung n140?

By default it gives me about 3 to 4 hrs on an 80% charged battery(Set through bios settings). The settings are said to extend the battery life if I am always plugged in. I am finding some other ways to prolong usage between charging though.