Questions about CPU's: quad core, dual core, etc.

Tim

Hello all, I was wondering if anyone could help me figure out some differences between all the different types of processors out there for computers. I am a graduate student learning about CFD, and my advisor wanted me to check out some different processors because we would like to get new computers. Currently in our lab, we use Fluent to model core flow for a rocket engine. Some other graduate students have set up four computers in parallel to run more complicated computations. However, a couple of computers are used regularly for desktops and simple calculations for teaching and learning Fluent for new students. I am not sure of all the specs for the parallel computers (I know they are Intel Pentium 4 3.0 GHz CPU, 3GB of RAM, using Windows XP), and I do not fully understand how this works. I just know that the computers in parallel split up the computations in order to get faster results for more complex models. The new computers will be used mainly for individual desktops. However, if possible, the new computers would be used to run some of the rocket engine models. We are not necessarily looking to replace the computers that are in parallel. We just have some extra money to spend and thought it would be nice to get new computers. One of my questions is what would be better, the quad core processor or 2 dual core processors. After researching some prices on pricewatch.com, I see that the quad cores are more expensive than the duo or dual core. Is there any benefit from using one quad compared to two dual/duo for computations? My knowledge is limited about the technology as well. From my basic understanding the duo/dual and quad processors are able to do more task than a single processor, correct? Can this be compared to two computers in parallel as well? Also, should we consider Intel's Xeon or Pentium 4 or a AMD processor? I understand the Xeon are for servers, but I do not understand what a server does and if using the Xeon is applicable for my situation. I also do not know much about the AMD processors. Finally, we have money to spend so price is not an absolute priority. However, we do not feel that the most expensive is necessary so we are looking at a few down from the top, i.e. instead of the $875 xeon 5080 we would probably look at the $200 5050 unless the 5080 is just really worth the extra $700. We plan on either buying the parts separately or going through a distributor such as Dell or HP depending upon their prices. Sorry this is really long but if anyone could point me in the right direction the help would be greatly appreciative!!! I also understand that some of the choices are personal preferences so if anyone has a similar setup or one they are really happy with please let me know! One last thing, I need some advice on the motherboards and video cards as well. Thanks! Tim