Have fun with your computer build. Not sure if you are a Windows, Mac, or Linux guy (assume Windows). However, when people say "cheapest PC" I always think of Linux...but that's only if you are a tweaker who enjoys setting up a computer and doesn't mind the code part (no matter what they say, every Linux build at home involves some level of troubleshooting). But you can put a good Linux computer together for less, all other things being equal (which they rarely are). From a quick Juli@ search:
Juli@ also provides 24-bit/192kHz coaxial digital I/O and a 24-bit/96 kHz optical output, 16 channel MIDI I/O and an E-WDM driver with DirectWIRE 3.0 functionality. The Juli@ is compatible with Mac (OSX 10.1 and higher) and Windows (98, 2000, XP, Vista, and Windows 7). It's also compliant with the Advanced Linux Sound Architecture (ALSA), so Linux users can get in on the fun too.
To be clear, I'm not advising you to go this route, just starting the conversation regarding Linux. When I made my similar choice, I found the previous generation (late 2009) Mac Mini to be more cost effective on the used market already set up for audio that just about any other system (I found somebody ditching their "old" system and looking to off-set some of their upgrade costs). I think I spent $400 for a Mac Mini with an SSD drive and extra RAM already installed. In your case, you are needing a case to add your card to, so this wouldn't work (I already had an external DAC).
Anyway, sorry to ramble...I guess I'm a bit chatty today. I look forward to seeing what direction you go....
Cheers,
John
John Kessel
Hawthorne Audio AMT K2 Reference Speakers
Paramount 300B w/MQ All Nickel Iron, Mundorf S/G 5.5 uF, and Vcap Teflon .1 uF
Auralic Taurus Preamp/Auralic Vega DAC/Auralic Aries Streamer
and lots of room treatments!