Have you decided on a budget and which compromises are you willing to make (eg if taking a relatively long time to render a scene using CPU instead of GPU in cycles is okay but you want fast physics based effects then you would probably compromise on GPU for sake of higher end CPU)?
Personally I went Linux since (1) I’d rather spend that $ on hardware and (2) I’m tired of Windows but I have to admit it was a bit of a PITA to get up and running; now I am happy though.
The computer in my signature was in that neighborhood including a pretty nice case. I prioritized GPU over CPU since this build is just for rendering (my son uses an i7 iMac for everything else).
If I were you I would look at the GTX 750ti graphics card, a lower end LGA1150 motherboard that supports SLI (so you can add a second Nvidia GPU later but don’t bother with the SLI bridge), 240 GB SSD, 8 GB RAM, 700 W or little higher power supply and best value i7 CPU that fits you budget. If you shop carefully you should have over $300 to spend on your CPU.
You could do without an SSD and buy a lower spec power supply but I don’t think these are things to skimp on - if storage is lousy slow or power supply doesn’t give you room to grow in the future then you will be less happy in the long run. Nice thing with the new Maxwell GPU is that they are very efficient so adding a GTX 970 or better should be possible later.
More cores does not translate exactly to better performance. Also, I believe the current generation intels are more efficient, which will lower your electricity bill. At that price I’d go with a i5, but if you have that much money to spend, I’d go with a i7 5820k. 8 GB will probably be okay, but 16 GB DDR3 wouldn’t hurt for heavy scenes.
As for the graphics card, for cycles it’s good to have more memory, so I’d choose a model with 4 GB. There are some 750 that have that. But for the money you want to spend, I’d choose a 970, which has 2.5 times the number of cuda cores. However, I believe the latest versions of Blender are getting similar performances on cycles between gpu and cpu, so maybe you don’t even need a very good graphics card for that anymore.
I’d also take the attention to buy silent stuff (power supply, graphics card, case, fans), as I hate having a turbine besides me.
Like starplayer says, I chose Intel in part because I wanted low power consumption / less heat to dissipate / quiet (my boss used to practically heat his appartment with an overclocked gaming rig that featured two SSD in RAID 0 and a water cooling system with external radiator - this was not what I wanted).
the GTX 970 is a very nice graphics card (based on benchmarks I would say best price vs performance ratio fot new cards) but I would wait til you spec out the rest of your build before picking which card suits your needs. The way I figure it, why spend $$$ on the graphics card if you spend relatively little time actually rendering. For $ you can still get respectable, such as GTX 750ti.
Also, if you are in no hurry (I spent a couple months reading specs, reviews, threads like this and looking for deals before I had everything and started my build), there should be some new AMD caards released soon that may put significant price and / or performance pressure on Nvidia!
In terms of raw performance, a r9 270 is much better than a GTX-750 ti. Unfortunately, OpenCL optimization in cycles is laughable, CUDA seems to work better, therefore any GTX will render faster in cycles if you render on GPU.
Also, if you’re on a budget, i’d go AMD. More cores does mean more power if the application is heavily multithreaded (and cycles is, i don’t know about the physics engine though). If you can go for an i7, though, they should fare better, because their better single-core performance coupled with hyperthreading gives them an edge, even on less cores.
I should add that in af FX there’s an FPU for each two cores, therefore the 8-cores FX, in floating point calculations, is really a quadcore.
If you are i5 vs 8-core FX, go for the FX i’d say.
I’m also thinking of building a Linux machine at around the same budget specifically for good Blender cycles performance, however, unfortunately, I haven’t built a machine from scratch before.
I’ve been doing some research online, and it seems that most of the guides for building machines are now over 2 years old, and so rather than follow an out of date guide, could anyone recommend a more detailed step by step guide to building a machine with a ramped up capacity for Cycles for a reasonable budget?
I think perhaps many of us would find such a guide really useful.
My advice is the same as last year: nVidia GPU is still about the only choice for Cycles rendering, as the CUDA cycles engine received much more attention.
Regarding cpu, for rendering i’d recommend an i7 with as many cores as you can get, if you can’t afford it then you may go with a top-tier i5.
The more lowly i5s (~3.3GHz and down) are actually surpassed (in rendering) by the octa-core AMD FX cpus, and, even better, the FX are unlocked for overclocking.
Likewise, if your budget is ridiculously big then a xeon with a ridiculously big number of cores is a good option.
A dual-xeon setup, even better, but then you’d need a bodyguard or two for your PC.
Rigid body simulations are single-threaded, therefore they’ll be faster on an intel cpu, even an i3, so if you need a CPU for rigid body more than rendering or fluids, then a low-end i5 may take precedence over an octa-core FX.
I’d still try to keep an i3 away from my pc though.
Some of this is blender-specific, and other rendering or simulation software may behave differently.