When considering what memory capacity is needed for a notebook PC, it is really quite simple - you can never have enough. Windows XP works perfectly well with 512MB RAM, but other applications may struggle, i.e. MS Office 2007. Rather, look for a laptop with a minimum of 1GB RAM. This should prove adequate for XP and most common applications. As for Windows Vista, Microsoft has stated the minimum memory requirement is 512MB. My experience tells me this is a pipe dream! Because unless you have a state of the art, discrete graphics card then Windows Vista needs a minimum 1GB RAM to deliver its seamless 3D graphics experience. Even with a top of the range Centrino processor, if you have only 512MB RAM and an integrated graphics card, Vista is not going to run at anything like the level of service you expect. Do not let anybody fool you on this, Windows Vista needs 1GB RAM - minimum, and for optimum performance look for 2GB.
As for those wanting to upgrade their existing laptop to maintain operability with modern software and hardware, it is important to know that laptops in the mid range price bracket only have memory capacity for a maximum of 4GB RAM. This is because such laptops only have two expansion slots that can hold a maximum capacity of 2GB each. With this in mind, a common tactic of many manufacturers is to enhance a notebook’s memory by using both slots. As 512MB RAM is cheaper than 1GB, 1GB RAM is cheaper than 2GB this saves them a fortune, but it does somewhat limit your memory upgrade flexibility. Basically, be careful if you see a laptop advertised with 1GB or 2GB RAM, it is more than likely that the manufacturer has installed two chips of 512MB or 1GB RAM, making expansion at a later date more expensive for you.
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