Those parts are pretty out dated, to be honest. You would have a difficult time quadboxing with that setup. The video card is pretty old (AGP), and I highly doubt the single core P4 could handle running 4 instances of wow at the same time while still being playable, and you would DEFINATELY need more than 1GB of ram. Perhaps I'm wrong though, I'm still relatively new to multiboxing

And as a side note, whomever told you that computer is worth 1300EUR is lying to you. It MAY have been worth that, like, 5 years ago, but today, not a chance