December 18, 2014, 01:47:55 am
SLI or Crossfire is not supported in Lumion. Lumion can only make use of one video card at a time.
The Benchmark reads system details from the DirectX reports. So it is likely that DirectX is seeing VRAM as the combination of the two cards, expected. So the 8GB VRAM is 2 times the 4GB VRAM of a GTX 970.
However, that does not explain why the score is so high. It looks like a doubling of 15000, which would be an expected score for a GTX 970. That may be something in how the Benchmark collates scores.
Results can vary depending on the rest of the system, for example if the system has a high-end motherboard and fast RAM.
And does GTX 970 and 980 are superior than Titan in the render?
Assume you are talking about performance and not quality.
Given the same scene rendered on each GPU, you would expect to see something similar (relative performances) to the results at Passmarks
. The Titans however have more VRAM and that suits the use in more complex scenes.
The Lumion Benchmark is a general guide. It does not test or reflect outcomes of the final rendering of scenes to image/video. It is useful in terms of comparing one card to another, as is Passmarks, that is the Benchmark indicates better performance for a GTX 980 than a GTX 970.
1. LUMION 5: Minimum hardware requirements
. (same for prior versions)
2. Lumion Web Site: Specifications
3. Passmark: Videocard Benchmarks