Forget Xeon. That's a much more expensive chip and motherboard requirement. I'm not familiar with CAD software but can't imagine it being too heavy on the CPU/GPU like say video editing and rendering software.
With that said, I wish I could list what I'd buy with that money, but MC's website is down apparently right now. Seems to be a frequent occurrence with them too. Generally I buy a CPU/motherboard there with a combo discount when they offer it. That's always been cheaper than buying from NewEgg.
However, I would watch their GPU prices vs. what you can buy from NewEgg. You'll likely spend more at MC even at face value, let alone sales tax. Same with the memory, power supply, and CPU cooler. For a CPU/Motherboard combo, this is...