Budget graphics card recommendation for Blender Cycles Render on Linux?

Question

I've started using Cycles Render in Blender for a specific project. I've set up CUDA on my Linux machine to enable rendering with the GPU however discovered that my graphics card, an old GeForce GT 520, does GPU rendering much more slowly than the render with the CPU (Intel® Core™ i7-2600K CPU @ 3.40GHz).

At this point, my budget for a new graphics card is R$800 (Brazilian Real) and this site is the cheapest local online market for cards.

Within my budget and in the GeForce line, I've found:

GTX 750 Ti 2GB

Geforce GTX 950 2GB

• Are these likely to improve performance significantly over the performance of my CPU?
• Or are they too low-level?
• Other suggestions?

Thanks

Answer 1

I have extensive experience with Blender and cycles.

The 750Ti is about 20% faster than your CPU. The 950 is about 100% faster than your CPU. (i.e. double the performance)

But currently GPUs render fur a lot slower than CPU, so take that into account if you work with a lot of fur.

With the CPU, you get the advantage of having access to all your system RAM (8GB, 16GB, etc). Whereas if you render with a 2GB GPU, it will not render a complex scene that requires more than 2GB RAM.

I would consider the 950, but not the 750Ti.

Source: GPU Benchmark, CPU Benchmark

Answer 2

Either of these options will improve your performance significantly. The i7-2600K gives you the Intel HD 3000 on-board graphics, and both of these cards outperform the functionalities of the Intel HD 3000 pretty significantly. As far as rendering is concerned, I had to do a bit of research, but for your purposes either of these units would improve your performance quite a bit.

Prior to Cycles Render, the GPU didn't really matter, it was all about having a beefy processor. Now, that Cycles puts the GPU to good use, buying a GPU for Cycles Rendering is a fantastic idea.

Now, as far as which GPU of those two to purchase, what you really want is a good chunk of graphics memory. Out of the two you listed, the GTX 950 would be my choice, although you get the same amount of memory, it is a newer card, and it brings with it all the features of a newer card.

From what I've read, 2GB seems to be more than sufficient for most people. That being said, a wise recommendation would be to download GPU-Z, render a scene, and see how much VRAM it takes to render. This will give you a better approximation of exactly what you need.

All in all, yes a GPU will increase your performance significantly, and the more VRAM you have, the better your performance when it comes to rendering with Cycles. CUDA is the preferred over OpenCL, making Nvidia cards the best choice. Of the two you listed, I would go with the GTX 950, which has a performance edge over the GTX 750 TI. If you're looking to save some money though, the 750 will still give you a significant boost in render speed.

Some sources: GPU Rendering FAQ | Blender GPU FAQ | GTX 950 Specs | GTX 750 Ti Specs