PSU for both of the builds are cr@p. I recommend you get a Corsair or PP&C. 2nd PC should work best (in pure performance vs. build 1) for heavy CAD work. You won't need very high GPU power, you can save $ by going with a 8800GS.
Thanks for the quick reply I am swapping the PSU to the following
PC Power & Cooling S75QB 750W ATX12V for $149.99
and also swithed the memory for the second setup to
mushkin 4GB (2 x 2GB) DDR2 800 (PC2 6400) for $186.99
Any suggestions on a video card
Looks good on PSU and RAM. To recommend on the video card I need to know EXACTLY how much work you will be doing. How many CAD models will you render at once on screen? How many parts/features for each model?etc.
Also is it absolutely necessary to spend $140 on case for 2nd build?
for the video card, since it is doing mostly cad work and such, no gaming. I would go with the quadro as it would help. I would stick with the original setup you had in post 1, but change the power supply, and up the cpu if possible if you plan to overclock as the lower multi might make it difficult. Change mobo as well to a p35, since you are not planning to use sli.
I think I am going back to the dual PC. As much as I would like to do the Xeon money wise it isn't in my budget. If I go the double pc route I can use one as the network pc, and also use it as a small media pc.