hey i have recently outgrown my laptop and decided to build my own computer...i will admit i dont really know that much about computers... i have had my lap top open a few times but nothing real serious.i am a computer science major but am in my early years and u know how that goes.. the first few years are all gen eds..... anyway to get to the real subject i purchesed a rather large AT tower off of ebay... and found out there is also a ATX.... whats the diffrence between the two.... am i gonna have less of a computer if i decide to go with a AT? is there certian things im gonna have to look for compatibilty wise on my hardware if i go with a AT? any comments or suggestions would be of great help... thanks....