Bottom line, the average user isn't going to notice a big difference (if any) between the performance of a Core2 Duo and and Athlon64  X2 system. Under the loads Poser, and other 3D applications put on a system, you will notice some difference. If your doing 3D professionally, then the extra $$ for a Core2 Duo system could easily be recouped on a large project. But, if you do 3D as a hobby, for fun, or moderately for work, then the extra cost associated with buying an Intel system may not be as important. Keep in mind, we aren't talking about huge difference in performance between the two.

AMD isn't The top performer any more, but the Athlon 64 X2 family are a very good value for your money right now.  True, if you have to have the "biggest, baddest, fastest" machine on the planet (for a couple weeks), you have to get a Core2 Duo. If you need a very good performer , and want to save some money, AMD is definitely the way to go.

Keep in mind that the whole memory speed comparison thing is like comparing apples and oranges.  The way the Athlon 64 accesses memory is much more efficient than how Intel does it, so data throughput with DDR2-533 on an Athlon would be similar to 1066 with the Intel method. In fact, even though the Core2 Duo has much better fragmented process data access/processing due to the larger processor cache, AMD still retains the lead in sustained (sequential) data throughput/processing. This is not reflected in the typical benchmark tests, as they tend to be very non-sequential, fragmented process intensive. 

I recently purchased a new AMD X2 system (laptop), and I'm very happy with it!  Yes, there are faster machines out there, but I saved a few hundred dollars on the processor, which enabled me to get a system with 2Gb of RAM and video card with 256Mb of dedicated memory.  If I went with a Core2 Duo, I would have had to settle for 1Gb of system RAM, and shared this precious RAM with a sub-par video card.  This limited RAM would have crippled the system so much that the even with  a "faster" processor it would have been painfully slow. 

Bottom line, I got a machine with a slightly slower processor (which at curret processor speeds is not a deal killer for me), but the extra benefits of more RAM and better video card, make it a more usable, and over all a better and faster machine than the equivalent priced Core2 Duo system. So, get the best system you can afford, knowing that in a month it would cost you less (maybe a lot less). With the systems you are looking at, your primary concern should be to get 2Gb of RAM (any more than that will have no benefit for Poser, which is stuck at the 1Gb thresh hold, but you need some extra headroom for the OS), and a good video card with a minimum of 256Mb RAM. Any of the AMD systems you looked at will be very very good with Poser if you have 2Gb of RAM.

Just my .00002 cents worth.

DR

PS: I'm not an AMD fan boy, I own and use both AMD and Intel systems. But I am a common sense, get the best value for you dollar/application fan boy, big time  :-)

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