I was in the same position as you last year. I wanted to build a system that would last for the next 10 years so I didn't skimp. I ended up spending around $2,700 CDN ($2,000US) and am very happy with my system. If you record anything with a mic and plan to have the PC in the same room you need to consider noise. A sound proof case, fanless graphic card and only SSD drives is what I used. I can barely hear my computer and it is 3 feet away from me. If you use a lot of virtual instruments then 32 Gig of RAM is good, I personally installed 16 Gigs and that is easily enough for my needs. You also have to consider connections for your audio interface. Because I wanted my system to use the latest protocol I decided to go with Thunderbolt over PC. Here in Canada I couldn't find a Thunderbolt equipped Mobo so I had to order one in from the US and it wasn't cheap. USB is fine for audio so I don't think this is a necessity. I did a lot of research and comparisons before buying the components, so if you don't have the time for that then buying a specialist audio PC is the way to go, as others have stated. I had my local computer store build it for me for a fee. I am a hobbyist working solely on my own music, and so far, knock on wood, my system has been rock solid with no issues. Good luck!