"best desktop music recording studio in the world"
Then you better get yourself Pro-Tools TDM rig w/ PT 888/24 I/O - Apogee AD-8000SE 8 channel Delta Sigma AD/DA - MixPlus3 Core - Mix & DSP FARM cards - USD Drive - SMTPC Lock Device - and why not through in a ProControl with some FaderPacks...only for a mere $50,000-75,000

IMO and from my personal experience, this is the best desktop arrangement currently available...or at least I've laid hands on.
First off...you better ask around on cubase.net/forum for compatibility between Delta series and the dual MP boards. I've yet to hear someone build such a system, so carefully approach this. If you don't know already, the digital audio workstation world is always a little behind in the times...lots of the pro sound card companies have yet to adopt drivers for the latest mobo/chipset releases. YOU MUST BUILD YOUR SYSTEM AROUND THE SOUND CARD>>> THIS IS A MUST OR YOU WILL GO THROUGH SOME VERY BAD TIMES!
I've personnally been through the Delta series (had 3 Delta 1010's running the I/O show for Logic Audio Platinum 4.7) and had nothing but rice crispie recording problems on an Asus A7V133 as well as on Asus CUSL2. ASIO setting adjustments were all over the place to obtain stable performance. Driver support is lame from my experience...it took them 5 months to get out multiclient drivers.
I now run the following system around ECHO Layla24's with track counts upwards of 55-60/w 2-3 plugs/efx per track including VST's here and there (Mercury, Waldorf,Pro-52 etc)...very cranking system!
2 x ECHO Layla24 (Rock solid...3ms latency ASIO)
Asus A7V133
AMD T-bird 1.33
512mb RAM
Adaptec 29160
2 x 18.2 GB 10K SCSI (one for audio/one for OS&progs)
Matrox G400Max Dualhead
2 x Sony G500's
I'm a progressive trance producer (serious hobbyist), and this is one of the latest home built rigs I've come to love. Get's the work done. I also am an avid Pro-Tools TDM user, but I leave the equipment at the studio...the PC is for home studio.
Let me give you some words of advice...do LOTS and LOTS of research before you jump into this. I've seen so many people pull there hair out after building the biggest bad ass systems because they were ignorant and failed do the proper research.
I'm going to tell you straight-out, I see a great potential for troubles using that Tyan MP board along with a high throughput 15k scsi drive...dont forget the sound card is going be accessing the PCI bus simulataneously as the SCSI drive...and a high throughput drive OFTEN causes pops while recording at bits greater than 16...you'll want to record at 24bit which is a lot of data to move. Often you will hear that people have to bump there controller speeds down to 20-40mb/s. I'm fortunate with my setup and feel that it is a result of excellent driver support/pci busmastering for the ECHO 24 series as well as the stability of the Asus A7V133.
You should be asking these questions at a pro-audio forum...no offense to the guys here, but almost 99% of them don't know anything about the DAW...it's a whole realm by itself.
Another reputable sound card company is RME. However for your needs, I feel the Gina24 from ECHO is going to be your best bet. They've just released the new WDM driver for win2k along with a newly designed mixer console.
Be smart, and don't rush into this.
GL.