New Computers

Hooking up a new computer is always so much fun-not! I have a Gateway laptop that has served me well (about 9 years old) but as you can image it doesn't have enough memory and it's just way too slow even to start it up let alone work with any current applications. So I purchased an HP with Vista (I have been very happy with XP). It's a slimline and very attractive. I opened the box hoping to find detailed installation instructions, and as long as someone is picture literate I guess everything works out just fine, but I really prefer words when it comes to installation. I finally hooked everything up. Now if I can just figure out how to integrate it wirelessly into my home network. I'm wired in right now but I'd like to be wireless. Do I need a wireless LAN antenna?