CPU vs GPU rendering Setup

Hi All,

How will a Dual CPU (Xeon processor E5 2630 v3, 8core/16 thread each, adding upto a total of 16core/32threads) rig with 32GB Ram, perform with Cycles CPU rendering compared to a Cycles GPU rendering on ‘single’ 6GB 2880 cores GTX Titan Black?

Should I prioritise my spendings for GPU renderings or Multi Core, Multi CPU rendering setup or both?

Note that this will be a modelling / rendering machine, with some amount of basic animations.
Primary focus of work would be for professional Architectural renderings. Max budget is ~$3000.

CPU specs: http://ark.intel.com/products/83356/Intel-Xeon-Processor-E5-2630-v3-20M-Cache-2_40-GHz
GPU specs: http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-titan-black/specifications

If that’s your choice, ABSOLUTELY go for the CPU setup. It will be nearly as fast, if not as fast, as the Titan, but without all of the annoying limitations of GPU rendering.

but with a 3k budget i would buy an eight core haswell (overclocking of course) not dual cpu setup

+1 with nudelZ

With a good processor and a good card you can use two process for rendering.

Pitiwazou: +1. Using two separate process does make good sense for multi frame renderings.
NudeIZ: Haswell will also make sense in long run. Checking out the i7 5960X Extreme Edition 8Core CPU.
Thanks All. Keep the suggestions rolling.

yeah, but still you will be bounded by the gpu rendering limitations (no sss, no smoke, ram limited). If you can afford such a dual cpu config, I wouldn’t think twice about taking the cpu. Also… isn’t the titan black a dual gpu with half the ram? Wouldn’t you be limited at 3gb?

Nope, Black has 6Gb Ram with single 2880 cores GPU. :slight_smile:

you are right, I was getting confused with the titanZ (which however has 6x2 gb).

Still… I prefer the cpu setup! :slight_smile:

I was actually wondering the same thing, with the same CPU’s but dual 970’s/980’s, however this applies just the same. I was siding with the CPU’s anyway based on other similar discussions in the forums, considering I am more focused on nature scenes with lots of particles and that appears to require a lot of memory, but I wanted to know how the CPU’s compared to a high-end GPU setup for render time since there are comments that the GPU will be much faster, better value and that its limited memory is not as limiting as is thought.

I also thought of the possibility of the new 8 core i7 instead, except in another thread asking for help with buying a computer someone mentioned that it only gives a 20% improvement in render time while costing much more than the next one down so is not good value. At the online stores I shop at this i7 costs almost the same as one of the mentioned Xeons, and the mobos I could find for the i7 are also the same price as most of the dual socket mobos, so I cannot argue this comment about the cost, but the render time I cannot verify. Just my opinion, but for the prices I found for these i7 & Xeon systems, what m9105826 said, and considering the CPU & mobo are the two most non-upgradeable parts in a computer, unless the OS or other software/drivers are an unreasonable hassle my choice will definitely be the Xeons.

This is really going to depend on the render engine you use. As I use Octane, I’m not up to speed on what Cycles will do, but with Octane you can use instances to keep your memory usage down to a reasonable level. This animation was rendered in Octane using only 1.2 Gbytes of vram.

It doesn’t matter if you are rendering on a CPU or a GPU, for nature scenes, instancing helps memory usage immensely. The limitations of GPU rendering are slowly going away as Octane and other GPU renderers start to support out of core rendering. You have about 10 to 20 percent speed slowdown when you run out of vram, but it doesn’t stop the render. I would suggest that you still put some money into a nice CPU, but do consider getting as nice of a GPU as you can. It doesn’t have to be top of the line, just get as much vram as you can.

For fun I costed out the Dual CPU setup, unfortunately in Australian Dollars (where I live), which comes to about $3250 USD in parts cost.

I got the following specs:
2x Xeon E5 2630v3 2.4 GHz 8C/16T 20MB Cache - 16C/32T total
4x 8GB DDR3 1600 MHz ECC Kingston RAM - 32GB Total
Supermicro X9DRi-F Motherboard - Supports multi GPU for future
ASUS GeForce GTX 750 Ti - For display
SanDisk 480GB SSD, Ultra II - Can be easily removed to save $150
Seasonic 1050W XP-1050XP - Great efficiency, modular and can support extra, or save $100 if went for lower version
Cosair Obsidian 900D - Choose a slightly smaller case if you want :stuck_out_tongue: Save $150

Knowing nothing about Octane but seeing it mentioned often in these forums, I took a look at it. I did not know it is a standalone different program, while it may be of benefit in ways over Cycles I am completely focused on learning everything Blender & Cycles, so tossing another level of complexity in is unfortunately not for me anytime soon, but perhaps it is more appealing to jadhav333. I wonder if Cycles will support out of core rendering in the near future?

If I gave the impression to anyone that I am thinking of going completely CPU-based I assure you that is not so. I just meant for the initial parts purchase my focus will be for the best CPU/CPU’s over the best GPU, it is easy to add extra or better GPU’s afterward, then I will have the best of both worlds. This is just my say on the subject. I am only window-shopping at the moment anyway, I will not be purchasing parts for a few months at least. How about you jadhav333?

I have yet to figure out how to fit everything in one post without it giving a blank white screen and disappearing.

Zeealpal; The cost of those Xeons is almost scary, is it not? That is why I am considering it, but without much knowledge of how different the OS, software & drivers are it is just a wish list for me for now. By the way, good parts choices! But jadhav333 may know more about dual CPU’s than me, and may decide to go that route yet. Keep us updated!

Also, the Corsair Obsidian 900D is one of the two cases I am considering for my future build, do you (or anyone else here) have one, or the 750D? I like my Corsair C70 but found the CPU area a bit cramped so want the extra room the 750D & 900D appear to have.

That is actually an important consideration, what case do you have or are you looking at, jadhav333? Sufficient room for building, modifying & upgrading is a key factor, as is adequate cooling. Especially with a high-end system like you are looking at.

No problem. :slight_smile: I only mention Octane because that is what I know and I needed an example. Cycles is improving all the time so I’m sure that it will have out of core features at some point. Octane also has a Blender plugin that is fully integrated so it works very similar to Cycles.

I have Octane and love it, however it has the same limitation (most anyhow) that you do with GPU rendering in cycles. Octane is really fast. I don’t currently use it in conjunction with Blender (I have plugins for other programs). When Octane Plugin announces they can render smoke and what not, I may consider getting the plug-in. Even so, there’s a free exporter and that’s how I discovered there’s not much gain in functionality compared to Cycles.

sorry - duplicate by mistake.

Octane devs do need to do some more work in the volumetric/particles rendering, they have actually removed some functionality (using textures with volumes). Otoy is going to have a big announcement tomorrow at GTC15, so we will see what they have planned for Octane in the next year.

Edited to fix the name of the conference. :?

I do not know about the OP, but the more I research dual Xeons, the more I cringe at the cost and unknowns (for me). I discovered the Xeons I was looking at are v2, not the new v3’s, and they are overpriced no less. Since I use my system for both Blender and general usage, and I am unsure if these CPU’s will be a problem for any games or other programs I use, I am putting this possible configuration on the shelf for now. I am not looking to purchase anything right now anyway, so have time to look for answers in my free time.

I must say those Haswell-E’s are looking very ideal, I found a review on a popular online store mentioning the 8 core is a rendering powerhouse (quite the opposite of the comment I read elsewhere in this forum). Definitely has me rethinking my future build.

Hope this helps!

There isn’t really any unknowns with the Xeons, they are CPU’s, just like the i7’s :slight_smile: Of course the platform they run on has more features (many your probably wont need) and most hardware for them is a bit more expensive.

2 8 core Xeons should render faster than the 8 Core Haswell-E, but if you add a good cooler to the Haswell-E and overclock it, you will get far better render speed vs $$ than the Xeons. Theoretically a 4.8GHz 8 Core Haswell-E will be similar to 16 (2x8) Xeon Cores at 2.4GHz., of course a 4-4.5 GHz Overclock is more likely to be attained.

Does Cycles rendering actually work like that? I read somewhere in the forum a while ago that the # of cores makes a much greater difference than the speed of the cores, but if not then the Haswell-E overclocked to 4Ghz+ definitely makes a lot more sense. The problem is sorting through all the posts in the benchmark threads to find such info, and not everyone uses the same OS or settings. I have been looking for actual comparable proof of whether the 5960X is worth the cost vs the 5930K for Cycles rendering, but have not found anything yet.