First I'll go over what aspects of a computer are important for performance in TG2, then I'll give you a rundown of an "ideal" system, and finally I'll do a quick example of something near the best price/performance ratio right now.
Please note 3 things. 1: TG2 performance characteristics and requirements are not necessarily the same as other high-end software. 2: This information is specific to Terragen 2 *right now*, and may change in the future (e.g. if TG2 becomes more efficient with many CPU cores available). 3: I am a Windows user so my recommendations will be slanted that way; fortunately the options are much more limited on the Mac side anyway, so there's a lot less to consider - just get the top-of-the-line and be done with it.
So, to begin with, the CPU is the single most important factor in high-speed rendering in TG2. Memory is important when rendering at high resolutions and/or rendering complex scenes, but raw speed is going to be almost entirely dictated by the speed of your CPU. It's also important to be aware that, even though TG2 is now multithreaded, a fast single or dual core will still often beat a multi-core CPU at a lower clock speed, because of the overhead of dividing the work amongst different cores. So for example a 3.2Ghz Core 2 Duo will likely beat a quad core at 2.0Ghz or so, even though the theoretical combined total performance of the quad is "8Ghz" vs. "6.4Ghz" for the dual core.
The quad core will also take more memory to render an equivalent scene when using all 4 cores because each core will need its own rendering cache. This is particularly important given that TG2 is currently a 32 bit application and limited to 2GB of memory use on 32 bit OS's and 4GB on 64 bit OS's (more on that later).
The last important piece of information regarding the CPU, which ties into the above, is that TG2 (and most other applications, but TG2 in particular at the moment) decreases in efficiency as the number of cores in use rises. For a single core CPU TG2 may achieve near 100% efficiency. On dual cores it's probably more like 85-90%. Quad cores, 60-75%. Once you reach 8 cores efficiency really starts to turn south, probably averaging 50-60%, meaning in some cases rendering on a quad core, or limiting to 4 cores in rendering, will get you the same actual speed, even though fewer processing units are theoretically being used. The overhead for using multiple cores just becomes too great. For this reason I recommend a fast quad core over dual or quad CPU's, unless you plan to run separate instances of TG2 on each CPU. Fortunately there is the possibility for a good deal of optimization here so in the future 8, 16, or more cores may be more easily recommended. But clearly, until TG2 is a fully 64 bit application, and further improvement is made to multithreading, anything beyond 4 cores is going to give you rapidly diminishing returns.
So, with the above in mind, I recommend getting the fastest quad core you can. Intel's new Nehalem (Core i7) CPU line is being released in November and promises impressive performance gains without having to increase the number of cores or the clock speed. So a 2.6Ghz quad core Nehalem will perform 20-30% better than an equivalent Core 2 Quad of today at the same clock speed. There is rumor that Intel will only be launching the "enthusiast" high-end, extremely expensive versions in November, but it's worth waiting to see if there will be more reasonably priced options in the same family.
For memory, the biggest impact will be in terms of the amount you have, not the speed. Memory speed will have little or no effect. The amount of memory will generally only allow you to render more complex scenes and at higher resolutions. More memory will not increase render speed under normal circumstances. The only situation where a performance increase might happen is if you have a limited amount of memory to begin with (1GB for example) and are using swap space on your hard drive, in which case rendering would slow down dramatically, and simply upgrading your memory could bring things back to where they should be in terms of performance.
Thus you should basically get the largest amount of memory you can, and not be too concerned about speed or type. Whatever is compatible with your motherboard and is available in large sizes (e.g. 2GB per memory module or greater). Memory is reasonably cheap at the moment so it's not difficult to get 8GB or more (though most desktop systems only support 8GB at present). There is little need to get more than 8GB for the moment anyway until TG2 is updated to be fully 64 bit and can support more than 4GB of memory itself. Of course having up to 8GB will still be useful since you can allow TG2 to take up a full 4GB while still leaving memory for other applications. Note that you will need a 64 bit OS to take advantage of all this (more on that in a moment).
The other key component for best TG2 performance and capability is the operating system. Personally I rather dislike Vista, so I'm inclined to recommend against it for the time being. But whether you get Vista or XP, you will want to get a 64 bit version to make full use of 4+GB of memory, and allow TG2 to use the most memory it can. Under a 32 bit OS TG2 can use *at most* 3GB of memory, and that is only with an unsupported operating system configuration switch that allows applications to use more than the normal 2GB of memory. In a 64 bit OS TG2 can use up to 4GB of memory itself, and no switches or configuration changes are necessary - it's completely "transparent" (i.e. "it just works").
Fortunately there are few downsides to going with a 64 bit OS at this point. There are a fewer driver concerns, depending on your hardware, but if you're buying a new system these are unlikely to be an issue as all your hardware should be supported. All your old 32 bit applications will run fine, and any of them that have 64 bit versions, or have "large address support" enabled like TG2 does, will also have the advantage of 4GB of memory (or more in the case of 64 bit versions).
Thus I'd recommend Windows XP x64 followed by Windows Vista Home Premium or Business x64, in that order. Some retailers will give you the best of both worlds with a "Windows XP Professional downgrade", where you get a license for Vista Business, but have XP Pro preinstalled instead, so you can always upgrade later.
All the other components are largely unimportant for TG2 performance, generally speaking. Most any modern graphics card will do fine, for example. The hard drive size and speed will have minimal effect as well. Do note however that some people have experienced problems with graphics system crashes under Vista. This apparently happens on both ATI and Nvidia graphics systems, though it is not necessarily widespread in relation to TG2. Just something to consider.
So with all that in mind here are the two system recommendations, configured at Puget Custom Computers because it's a lot easier to get a good custom build than through someone like Dell, though I would not necessarily recommend them as they carry a price premium (a home build will get you the best price/performance mix if you've got the ability):
First the "ideal", high-end, which you are warned will be higher-priced than its performance advantage justifies (this is always the case with "premium" hardware). Note that I have only gone "to the max" on the items that will affect TG2 performance; you could easily configure a more expensive system that would perform higher for other tasks like gaming. I have not included a monitor as I assume you already have one. Also keep in mind that Nehalem may change this recommendation very soon:
http://www.pugetsystems.com/?u=11306Cost: $3650
Key Features:
3.2Ghz Intel Quad Core QX9770 CPU
8GB of RAM
Windows Vista Home Premium 64-bit SP1
So in this case note that you are paying an $1800 premium *just* for the CPU, as compared to an equivalent quad core at 2.33Ghz. At 3.2Ghz/core, a difference of 870Mhz/core, or about 35% faster clock speed, you're paying quite a lot more than 35% more. In fact if you went with a 2.3 or 2.6Ghz quad, you could get *two* computers at that speed for the price of one at 3.2Ghz. Even 3.0Ghz can be had for $1350 less, so that's probably your "sweet spot". But again if you want the maximum possible performance in a *single* system, this is it.
Now for the far more sensible option, the "sweet spot", mid-way between budget and extreme performance. This is the best bang for your buck:
http://www.pugetsystems.com/?u=11307Cost: $1720
Key Features:
2.83Ghz Intel Quad Core Q9550 CPU
8GB of RAM
Windows Vista Home Premium 64-bit SP1
Aside from the obvious change in CPU, I also switched to onboard graphics, which reduced the price a bit more. The onboard Intel 3100 should do ok for TG2, although I'm not positive of that.
So obviously the price difference is huge, and meanwhile the performance of the 2nd machine will be reasonably close to the first. Get 2 of machine #2 for the price of #1.
If you build it yourself you can shave several hundred dollars off of both configurations as well.
As I said at the beginning these are configurations for TG2's *current* performance characteristics. If multithreading becomes more efficient in the future, you may want a dual CPU system, which you can buy now with a single CPU and then add a 2nd CPU later. That's something to consider...
If you have any more questions let me know.
- Oshyan
