I'm looking to buy or build a computer that would perform well making models and doing some FEA of parts. I'm already planning on a having a GPU like a PNY FX1800 unless there is something in the same price range and is better or something less expensive and just as good. I was looking at HP Pavilion's like this one http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=5501888&CatId=5140, the specs on it look to be an ok platform just missing a good GPU and possibly a better HDD. I guess mostly I wasn't sure if a HP Pavilion like the one that I posted would be a good computer to start on or if I should build one from the ground up. As for my price range I was thinking up to about 900 dollars or so and I already have a good monitor so no need to include that into the build.
FEA as in Finite Element Analysis? If so, GPU will NOT make much of a difference (unless running CUDA/STREAM based code). What you need is a OCed Quad with plenty of RAM. If budget allows, get a i7 920 (easily OCed to 3.6-4Ghz with a good cooler with HT on) + 6GB+ DDR3 1600.
Again, unless doing renderings (or really complex parts), GPU won't make much of a difference in CAD. The point is, you really don't need a workstation card (a cheap 4650,etc will do).
You'r better off with a DIY build as you'll be able to upgrade/OC down the road. Also, what programs? Inventor?SolidWorks? Alibre? Solid Edge?
Yeah I'm just wanting a good GPU for making models on either Inventor, Alibre, or Wildfire 4.0. I don't think any of those can utilize a multi-core processor but if I do FEA or anything else while using a solid modeler I think I will want a multi-core processor.