ISBoxer's official minimum specs and recommendations: http://isboxer.com/wiki/Multiboxing#...m_Requirements

Most of what people are recommending is pretty much optional. For example if you have extra money to spend purely on added LOADING performance (*NOT* framerate) or whatever while multiboxing, then certainly get an SSD; if not, don't worry about it, we've multiboxed without them for years. Generally when I have time to multibox I am doing it on my $1200 laptop -- the ASUS G74, with an i7 CPU, 560M 2GB GPU, and 8GB of RAM. Everything about it is stock, straight from Best Buy. I can put my main on high or ultra settings, and I put the others on low, and I have been quite happy with its performance.