Seeking DAC $300

I was thinking a little more about it. How much SHOULD I spend? My limit at $300 is pretty arbitrary. Would I notice a lot of difference if I spent say $500? or $700?

With the Gungnir, how would I set it up? I have a SPDIF connection on my motherboard but isn't that tied to the internal sound card that I want to avoid?

Thanks for all the suggestions - I have some research to do!
Any thoughts on the Ifi Idac?

Thanks Polyglot.

I was seriously looking at the EE MiniMax but then realized that the USB connection only goes to 48Khz. The new Minimax can handle 192khz but it's $1,000!

I removed the Bifrost from the list after reviewing the manufacturers comments on their USB implementation. They basically say they didn't put much into it.

Since I plan to use the USB connection, I've been looking at the iFi iDac and the Micromega MyDac. Any thoughts on those?

I ordered the Micromega MyDac and iFi iDac with iUSB. We'll see which I like better.