Before you spend the bucks to build or buy a new computer and all the time involved in setting it up for audio......
Just go and buy a new Focusrite Interface. You might spend between $150 to $250 dollars on it. But, you have a new interface and then be sure you upgrade the ASIO driver per the factory.

Aren't those Delta things pretty old and have the octopus looking mess of wires coming out of the back? Or am I thinking of something else?

BUT..... before you do that..... just wanted to check on something....

Be sure you're not trying to run your DAW and BB and or RB all at the same time thinking you're using ASIO for them. ASIO will only support the first one of those programs you load. Everything else gets MME or whatever else is available but it won't be ASIO. Perhaps you already know this. It catches me off guard occasionally. If I try to do playback on an audio/midi project it's a mess.

Actually Sonar warns me that ASIO is not available but BB/RB doesn't and will let me try to playback something that won't playback nicely on MME.

You can find my music at:
www.herbhartley.com
Add nothing that adds nothing to the music.
You can make excuses or you can make progress but not both.

The magic you are looking for is in the work you are avoiding.