If you have gobs of money, buy everything new, two of the HyperThreaded 18-core Xeons and two Xeon Phi co-processors for PCIe slots. Obscenely powerful, but that will cost cubic dollars.

If you're on a budget, look on eBay for surplus/refurb enterprise gear. Search terms could be "2x X5650", also check X5660, X5670, X5680, and X5690. The higher the number, the faster the clock speed. In Xeons, "E" are economy power-saver models, "L" are a balance of computing power and economy, and "X" are the high performance models. You want X. Although, H/T quads like L5520 are absurdly cheap now, and two of those would give you sixteen moderate speed render threads. All of the X5650 through X5690 models are heavy duty HyperThreaded hex core Xeons; a pair of them in a workstation gives you 24 render threads. Chassis which came with these processor packs include Dell T7500 and HP z800. The smaller midtower versions are T5500 and z600.

Server/workstation motherboards use registered memory (often called server memory), although they generally can use common gamer memory. You can use more RAM if it's registered. Basically, this type of RAM has an extra chip which functions as a memory controller, relieving the CPU and north bridge of a big share of the burden. It often has error correcting code (ECC) to increase stability. It often has metal heat spreaders to help cool it.

Look for a used workstation with dual Xeon processors and 36-96 GB of RAM. Figure on supplying your own hard drive(s), since you can't count on a used hard drive. You can get a 64bit Win7Pro OEM license for $75-$120.

Beyond that, you might add a better video card (or cards, if you want to GPU render), and you can add PCI/PCIe cards to give it eSATA ports and/or USB3 ports, if you want them.

I have $1260 in Urania, and she has 48GB of registered ECC RAM with heat spreaders and dual X5660 H/T hex Xeon processors (24 render threads), and a Quadro FX3800 video card. Compared to what you'd get in a new gaming PC for $1260, Urania will kick the gaming machine to the curb when it comes to 3D rendering.

dual X5690 on eBay . I specified T7500 and z800 in the search along with "2x X5690", because if you search for just the processor you'll get a lot of blade servers and bare processors. The blade servers are great as render slaves -I have several- but their form factor is not suited to use as your desktop computer.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

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