Help on Choosing a GPU for Iray

DAZ_Spooky

Havos said:

Ah, now I understand the question. I am not 100% sure, but I would have thought that the output resolution size would have little or nothing to do with the amount of video card RAM needed. I guess the final image would be kept on the card somewhere (though I am not certain this is correct, it may be in main memory only), however, either way the memory needed for a single image will be irrelevant compared to all your scene textures etc, which will be loaded in regardless of output image size. I suspect (but again I am not certain), that some off screen assets would not be loaded onto the card, but that would be independent of the output resolution.

It impacts the card displaying the image, which may or may not be a card involved inthe render. It has a lesser impact on the cards doing the render, if they are different. In both cases the impact is relatively small, unless you go to extremes. 

DAZ_Spooky

ronmolina said:

timmins.william said:

Load larger and larger scenes. If your card melts and sets your computer on fire, it wasn't big enough!

 

I actually had that happen about 5 years ago. I believe the fan on the video card failed when I was rendering a Vue scene for several hours. It was an old card.

We had a tester using an external case for Video cards, and a ground cord got, accidentally, cut. Burned up three cards. 

StratDragon

fastbike1 said:

While I think a beefy power supply is a great investment, I'm not sure folks realize that the current Geforce cards only need from 140 to 250 watts each.

Older (than the current offerings) Geforce cards are hard to find and typically almost as expensive as new. If you need more than 4GB for a scene, your only choices in new cards are the GTX980TI and the Titan X.

Titan X in the US is ~$1000, the GTX 980TI is ~$650. The 980TI has almost as many CUDA cores (2816) as the Titan X (3072), but half the memory (6GB vs 12Gb).

I wouldn't recommend less than the GTX970 if you are getting a new card for an older (<2 years) machine. The 970 has 4GB of memory (960s and below have 2GB which won't be enough) and 1664 CUDA cores. Costs about $340 USD and needs 140watts.

I wouldn't consider a 980 because it's only $100 less than a 980TI but only 4GB and 800 less CUDA cores.

3D rendering has always been hardware intensive. You pays your money and you makes your choice.

But they need it from PSU's that provide well over those levels as failure to provide these cards with the consumption requirements they require could damage them or the rest of your system permanently. Power consumption from the last few generation of Nvidia cards has changed little but power requirements are still remain well above that threshold as the manufacturer states.

For a Titan X Nvidia suggests the minimum size of the PSU in your desktop should be powered by no less than a 600 Watt PSU
http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-titan/specifications

and the 960 is at the very least requires a 400 Watt PSU
http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-960/specifications

If you stick a card that maxes out at 120Watts of power in a case with a 350W PSU because you supplement wattage consumption with power requirement you could turn your rendering box into a smoldering brick doorstop.

 

 

Bobvan

I just popped in a GTX980 with 2 1/2 yr old 32G system and using 890M on ROG 24G laptop big scene multiple figures no problem dont even need to hide or delete any from scene to scene. I am getting some strange color bug on the 980 I tried some stuff suggested on the net to no avail. (Resolved with nvidia support)