I have an Alienware M17x and wanted to check if I can buy Windows 7 Home premium and upgrade it on my computer... My friends who work for some hardware outlets told that Alienware has a different windows 7, but not the one which is compatible for all computers. Please respond to this...
Your friends may be referring to the fact that it's an OEM copy, which will be true for any pre-built PC you buy. OEM licenses can only be used on their respective computers, whereas with a retail license, it can be installed and uninstalled from any machine and moved to any machine (but only used once at a time).