What is better for cycles rendering? Very Powerful CPU or mid range Video card?

Support Lighting and Rendering
#1

I have a choice between a very powerful CPU or a low-mid range Nvidia Video card. I know that cycles render can use either CPU or GPU. I have two choices below and need to know which on is a better choice for cycles rendering in blender.

Choice 1: AMD 8320E 8-core CPU at 3.3Ghz. If I go with that powerful CPU I cannot get a video card and will be using that CPU to render in cycles.


Choice 2: AMD A6 7400K 2-Core at 3.9GHz paired with a Nvidia GT 720 192-core (Cuda Cores) 2GB video card and i wil be using that video card to render in cycles.

evga_geforce_gt_720_0.jpg800×800 190 KB

I guess my main question is: Is a GT 720 192 Cuda Core Graphics card more powerful than an AMD 8320E 8-core CPU when it comes to rendering in cycles?

#2

Just for the record: The FX-8320 does not qualify as a “very powerful CPU” - in fact, it’s rather mid-range and might not even be able to hold its ground against Intel’s current i5s.

However, when compared to the rather low-end GT 720 it might still be the better choice, especially since the GT 720 maxes out at 2 GB VRAM, which is a bit on the sparse side. If a scene does not fit in the card’s VRAM, it will not render at all, so you will be stuck with your 2-core CPU…

#3

How complex of a scene would it have to be to max 2GB? currentlu im trying to render a full room scene complete with objects like glass and i want to render at 1000 - 2000 sampling. would that max 2GB? or even 4GB?

It looks like my best choice is a 4GB video card or a AMD 8320 or Intel i5.

EDIT:
I found this: EVGA GeForce GT 740 Superclocked 4GB PCI-Express Video Card 384 cuda cores

would you recommend that over the AMD 8320 and intel i5 4670K for cycles rendering?

#4

We’re seeing a tendency in Cycles to use more and more VRAM on rendering with every release, due to the constantly increasing size of the CUDA kernel (more functions = larger kernel). So, it might not take that much of a scene to quickly fill up 2 GB VRAM…

I for myself would not buy 2 GB cards any more, but that’s perhaps just me. Looks like indeed the FX-8320 might be your best option. Switching to Intel would mean switching the mainboard as well (different socket).

#5

I only have 4GB system ram and wont be able to get anymore for a while, Since my system memory is only 4GB would a 4GB GT 740 (384 cuda cores) be the way to go over the AMD 8320?

My guess would be since the system memory is running at DDR3 and the video card memory is running at GDDR5 the video card wins?

#6

I went with the GT 740 and couldn’t be happier : ) It renders surprisingly fast and with 4GB GDDR5 memory i wont have to worry about crashes when rendering a full scene.

#7

From what I’ve messed around with.

Small simple scenes go with GPU. Super fast.
Larger or more complex scenes go with CPU. It might be a tiny bit slower depending on your chip but it’s much harder to find your system limits on CPU.

#8

I’d say it depends on what you want to render. For simple scenes with simple geometry, I’d go with GPU because it is often a lot faster. But if you need to render particles or hair or some effects which are not supported by GPU (SSS, for example), CPU would be the better choice.