Question GTX 970 vs Ryzen 5700G for 3D architectural rendering ?

[Pimpom]

I've ordered the parts for a new desktop for my architect son who's just starting out on his own after working for some time in a small private firm. His work so far ranges from small one-floor residences to an eight floor building, with the occasional church and community hall thrown in. He uses AutoCAD for drawing and V-Ray for 3D rendering.

At this point 3D rendering is not a daily task and I thought a Ryzen 7 5700G with 2x8GB RAM would be a good compromise between cost, power and capability for light gaming. Then I found a used GTX 970 for a good price and am wondering how much of a difference it would make for the rendering part. That is, GPU rendering with the GTX 970 vs CPU rendering with the 5700G. Experts please.

 

[Hellfire13]

It will make a huge difference. The 5700g comes with Vega 8 iGPU which is around GTX 1030 level performance, maybe a tad better but basically still entry level. Where as a 970 is way better in performance.
Here is a rough comparison...
https://gpu.userbenchmark.com/Compare/Nvidia-GTX-970-vs-Nvidia-GT-1030/2577vsm283726

 

[Pimpom]

Thanks for the reply. I have an idea of where the GTX 970 stands among reasonably modern graphics cards. I also ran comparative benchmarks of Vega 8 against the 970 and other GPUs. What I'm not sure of is how such benchmarks translate to architectural rendering.

 

[Pimpom]

A vital point that cannot be clarified by theses benchmarks is that the question is about GPU rendering with the GTX 970 vs. CPU rendering with the 5700G, not with the Vega 8 graphics engine which is in no way comparable to the 970.

 

[Eximo]

Still would heavily favor the CUDA cores in the GTX970, it just has much more parallel processing capability. Would really depend on the software in question.

If I were going to buy a GPU for this, 970 isn't what I would pick. For not a whole lot more I would track down a Quadro M4000. Same GPU, but double the VRAM and ECC. Both can be had for roughly $70-80 on occasion on ebay.

 

[Hellfire13]

Thanks for the reply. I have an idea of where the GTX 970 stands among reasonably modern graphics cards. I also ran comparative benchmarks of Vega 8 against the 970 and other GPUs. What I'm not sure of is how such benchmarks translate to architectural rendering.

GPUs are better in rendering because they are optimised for graphical compute and parallel processing.They can process more tasks simultaneously, than a CPU.

A vital point that cannot be clarified by theses benchmarks is that the question is about GPU rendering with the GTX 970 vs. CPU rendering with the 5700G, not with the Vega 8 graphics engine which is in no way comparable to the 970.

Whether it is the 970 or the vega 8 the CPU will play the same support, maybe a bit less efficiently with the vega 8 as it shares the same die. The render will happen through the GPU only and hence depends on the strength of the GPU.

 

[Pimpom]

Whether it is the 970 or the vega 8 the CPU will play the same support, maybe a bit less efficiently with the vega 8 as it shares the same die. The render will happen through the GPU only and hence depends on the strength of the GPU.

Is that true? My understanding is that, with CPU rendering, the CPU bears the brunt of all the calculations necessary to form surfaces, shades and textures from vector elements whereas it's the GPU that does most of the work with GPU rendering. A simplified description, to be sure, but that's the gist of my understanding.

 

[Pimpom]

If I were going to buy a GPU for this, 970 isn't what I would pick. For not a whole lot more I would track down a Quadro M4000. Same GPU, but double the VRAM and ECC. Both can be had for roughly $70-80 on occasion on ebay.

Unfortunately, I don't have access to such sources. We no longer have eBay in my country. A greedy online company bought it and killed it outright. They did the same thing with another competitor several years ago.

We have only one other source for used computer parts - a forum that's very active but the last time I saw a used M4000 Quadro there, it was offered for three times the price of the used GTX 970.

My son's computer will eventually be fitted with a good graphics card. The 970 is meant to be a stop-gap.

 

[Hellfire13]

Is that true? My understanding is that, with CPU rendering, the CPU bears the brunt of all the calculations necessary to form surfaces, shades and textures from vector elements whereas it's the GPU that does most of the work with GPU rendering. A simplified description, to be sure, but that's the gist of my understanding.

I was talking about GPU rendering only, vega 8 vs 970. Not between CPU and GPU rendering. Its not optimal to use your CPU for rendering when GPU processing is available, unless otherwise stated.

 

[Pimpom]

I think we have a communication gap here. The whole point of this thread is about the difference between rendering with the 5700G as a CPU, not the Vega 8 it comes with, and rendering with the GTX 970.

Case 1: Ryzen 7 5700G machine without a discrete graphics card. Since the Vega 8 IGP is puny as a rendering processor, CPU rendering is selected. The CPU part is used as the rendering processor while the Vega 8 IGP does the job of displaying the result on the monitor.

Case 2: A discrete GTX 970 is installed and GPU rendering is selected. The GPU does most of the calculations and also acts as the display driver.

 

[Eximo]

Most of what was said still applies.

8 generalized CPU cores with SMT allows 16 simultaneous calculations at perhaps 3.6 to 4 Ghz.

GTX970 with 1644 processing cores running at 1600-1800Mhz, and much more specialized at mathematical calculations, will get the job done maybe one order of magnitude faster, if not more. Particularly with something like V-Ray. I would not be surprised if the Vega 8 can't also outperform the Zen3 cores.

Vega 8 has 8 GPU cores with 32 TMUs, compared to the GTX970's 104. Not exactly one to one, but depending on how the job is processed by Vega, it could be faster than the CPU.

But you would have to use OpenGL or OpenCL for the AMD graphics while you have native CUDA processing possibilities with Nvidia. Though AMD and Nvidia are matched here in OpenGL support, for some reason AMD only supports OpenCL 2.1 vs 3.0 on the 970, wouldn't have called that. They also both support Vulkan, but I don't think that is used much in static renders.

 

[Pimpom]

Thanks for your interest and input. I expected to hear that the GTX 970 will be significantly faster than the 5700G for rendering but wanted informed confirmation (or refutation if I was wrong). Data about static rendering is much scarcer than game fps.

My son is currently using a Lenovo laptop that I bought for him 6 years ago when he was in college. It uses an i7-4710HQ and a GTX 860M. The 1TB HDD still doesn't have a single reallocated sector count but I replaced it with an SSD anyway (SATA as it doesn't have an M.2 slot) and also maxed out the RAM to 16GB. He uses a 27-inch monitor when he's working at home. I was rather surprised to see that there's little difference between CPU and GPU rendering.

 

[Hellfire13]

I was rather surprised to see that there's little difference between CPU and GPU rendering.

Well, that is because compared to that CPU, that 860M is a potato.