How To: Building Your Own Render Farm

Hardware Component Selection For Each Node

Processor selection is dependent on two things: how much you're able to spend and resulting value. Even more so than normal desktop systems, render nodes are sensitive to these factors. There is a certain point on the processor performance curve where the next increment in compute speed results in a pricing jump that is out of order with the increase in performance. However, with today's higher bus speeds, too little cache on a processor can leave it starved for data. So, for discussion's sake, we'll shy away from Celerons as the bottom-end processor and instead use low-end dual-core Pentiums.

Using a lower-cost dual-core Pentium can give you a very inexpensive render node with a minimum sacrifice of performance. The Cinema 4D Release 10 chart shows the performance curve. While dual-core Pentiums and Celerons are not in these charts, you can see that there are spots in the Intel processor lineup where there is a significant jump in price for very little increase in performance. Find the price that you are willing to pay and then look at the best performance for your price range.

A dual-core Pentium, a slightly faster Core 2 Duo, or even a low-end Core 2 Quad are all good choices for building a node. It's really all about how much you want to spend here, because this is the single most expensive component required for each node. At the other end of the spectrum, building a Core i7-based system is going to increase the price of the entire node out of proportion to its increased performance. However, if you want to moderately future-proof your nodes and increase the likelihood of being able to get a processor upgrade for it later, you may want to consider that route.

A low-profile 1U heat sink is required for a corresponding case, most of which are made to specifically draw air from the front to the back of the machine. The limits in choices in processor cooling also limit (or even restrict) the possibility of overclocking the nodes. The Dynatron P199 pictured above is fairly typical and can handle quad-core processors.

Storage

Because the local drive will just be used for your operating system and applications, pick a small drive. An 80 GB drive is the smallest SATA drive commonly available, so that's what we recommend. However, if you use a drive with a digital audio workstation (that setup is discussed below) then a 320 GB, or maybe even a 500 GB drive, is a better choice.

Assuming you are building multiple nodes, you are only going to buy a single DVD drive (even if you are building 10 systems). You'll build your first machine, install the operating system plus software with updates, and then use Sysprep to blank the registration number. Next, use Norton Ghost 14 or similar drive-imaging software to clone the disk for subsequent machines. Each new system will require a fresh network name, and you will have to enter the Windows license key for each of the cloned machines. This keeps you from having to install the operating system, the applications, and the updates on each of the machines separately. If you build additional nodes using the same hardware in the future, it's also a good idea to clone one extra drive and keep the original as a master drive.

The operating system for your nodes should be similar (but not necessarily identical) to your operating system. Since 64-bit Windows XP is still available through OEM channels, there is no need for you to even consider putting Vista on your nodes, wasting memory and processing power. If your 3D application's network renderer (and all of the plugins that your network renderer needs, including third-party plugins) are supported under Linux, you may want to consider running Linux on the nodes instead, which makes the nodes even cheaper. A total of 10 copies of XP (for 10 nodes) may sound like a big expense, but it actually adds $140 per unit, pushing the cost of these machines to about $485 per unit for a dual-core node or $610 per unit for a quad-core configuration.

So here’s what we’re looking at for a per-node price, with both dual- and quad-core processors. Remember, these are prices we found when this article was written, and they should change in the near future.