New CAD/CFD build

Hello all, just wanted to see what people thought about this build.
The PC will be built by (but he will pay for it, I'm just not charging for the build time) me to a neighbor because he is helping me out with some CAD work (See my Custom Waterblock thread). This will be replacing a 2P Intel Xeon 7040 build.

The build will be used for pro level CAD/CFD, mostly CFD. The CAD models will be imported from a different PC. The CFD software will be: FlowWorks(SolidWorks), CFDesign (Inventor) and Thermal Desktop (Inventor). Because it will be mainly CPU intensive and the actual models won't be created on this PC, there is no real need for a workstation GPU.

The budget for this build is $5000-6500, excluding S&H,etc. Everything will be bought from Newegg, unless there is a huge difference in price for the same product elsewhere (but the site HAS to be reputable like Newegg).

This is what I'm thinking:

RAM: SUPER TALENT 6GB (3 x 2GB) ECC Registered DDR3 1333
http://www.newegg.com/Product/Prod [...] 6820609458
$180

MOTHERBOARD: SUPERMICRO MBD-X8DTL-i-O Dual LGA 1366 Intel 5500
http://www.newegg.com/Product/Prod [...] 6813182189
$330. Any one have better recommendation for a 2P Nehalem board?

CPU: 2x Intel Xeon E5504 Nehalem 2.0GHz LGA 1366 80W Quad-Core Server Processor
http://www.newegg.com/Product/Prod [...] 6819117187
$229 (each); $455 total

HDD(DATA): 4x Western Digital Caviar Green WD10EADS 1TB SATA2
http://www.newegg.com/Product/Prod [...] 6822136317
$79 each; $315 total.
These HDDs are going to be in RAID5 for a total of 3GB. The reason For 3TB is the simulations will be saved ~ every 50-100 iterations. Typical simulation will run for ~ 60000 iterations. Each saved iteration point is ~20MB so a full simulation is ~ 25GB. After the sim most of the saved will be compiled in to one result file (~1-2GB).

HDD (OS): VelociRaptor 150GB
http://www.newegg.com/Product/Prod [...] 6822136296
$180
Only the OS and programs here.

PSU: PC Power & Cooling 910
http://www.newegg.com/Product/Prod [...] 6817703022
$185
Only because I need atleast 2 8 pin CPU. Any one know where to buy Molex to 8 pin CPU? I can make it myself, but that's a bit of work.

Case: Antec 902
http://www.newegg.com/Product/Prod [...] 6811129058
$130

Graphics: ATI 4670
http://www.newegg.com/Product/Prod [...] 6814121274
$70
Mainly because, I doubt the onboard GPU can handle 3D well with out lag.

Already have: LCD, DVD RW, OS (Server 2008 or XP x64)
Total: $1868, still below my budget.

What I need:
1. A good RAID card with RAID 5.

2. A lower priced (and good quality) PSU with a 2x 8 pin CPU connectors.

3. Is everything compatible?

4. Any recommendations on a good (possibly silent) HSF for a 2P system?

^Yeah, I know, any recommendations? The reason I didn't get the E5540 is that the extra 530Mhz wasn't worth the extra money. For what this will be used it would only make it about 10 minutes faster. As the simulations are usually run over night, there is no reason for the extra cost.

I was also thinking, would a 4P (Core 2) make sense than a 2P Nehalem for this kind of work? Either way, this is a huge step up from the 2P he was using earlier.

The sim software (mainly Thermal Desktop), for some reason don't benefit from speed increase (not sure about the core # increase) after a certain point (in the designs sims he run). The benefit, for example in a Q6600 @ 3Ghz is almost the same as that of a Q6600 @3.6Ghz. Only a few minutes difference on the results for some reason. I think this has more to do with the Auto optimization of the cells,etc at certain clock speeds. For the Q6600 @ 3.6Ghz, the result (time step=~.00000001s) was smaller, meaning higher detail than the Q6600 @3Ghz (time step = ~ .00001s). After a certain point, the accuracy/precision is insignificant for the real world application that are being simulated.

^I was thinking about that.

A D5 + 2*GTZ + 2x320 rad should work.