Or do you want to record multi-track music with Cubase? If so, get the best you can afford: the quickest CPU (dual CPUs would be better but if you use the newer P4 hyperthreading CPUs they act as 2 CPUs anyway (like the server Xeon CPUs). So 2 hyperthreading P4s act like a quad system and XP pro only supports 2 CPUs), the most RAM and the fastest hard drive (I use a SCSI hard drive). I guess you could build one cheaper than the Carillion systems yourself (mine is an old dual PIII server board with 1 GB RAM, 2x PIII 800 MHz CPUs, a 36 GB SCSI HDD and an Audigy sound card. I only record audio (not MIDI) and it works a treat. Recording music is essentially just doing vast amounts of number crunching so the bigger and faster the PC the better.