Ahhh congratulations! I remember when I got my hands on my 4000... it had been a dream for me as well since the early 90s... always out of reach, then a few years ago, I sold my 1200 tower and got a slightly less powerful 4000. I didn't regret it one bit! The 4000 is a brilliant machine.
Of course, since then i've put it in a tower, added a PowerFlyer Gold, a Repulse, Mediator 4000, Cyberstorm MkIII 060, and a load of other cool things.
I love it, and I hope you get as much use and enjoyment out of yours as mine has given me over the years.