More than one GPU
Pick the card a bake runs on, mesh a liquid's surface on another card, and solve a big liquid or smoke over several cards.
With more than one NVIDIA card, Bake Settings shows a few more settings. Each card is remembered by its own ID, so a picked card stays picked when the driver lists them in another order.
GPU: which card bakes
GPU picks the card a bake runs on. Left on the first choice, a bake takes the first card that can run it, and background bakes spread over the cards (each to the one with the fewest bakes). See Several simulations at once.
If a picked card is gone (the file opened on another computer), the bake says "The GPU picked for this flow isn't in this computer: pick another, or set Compute to Auto".
Surface On: where a liquid's surface is meshed
A liquid's surface mesh is made each frame, beside the simulation. Surface On says where:
| Choice | Meshes |
|---|---|
| Auto | On another card than the bake's when there is one; else on the bake's card; else on the CPU |
| Same GPU | On the card the bake runs on (the CPU when the bake is) |
| GPU | On the card picked in Surface GPU |
| CPU | On the CPU |
The mesh is the same wherever it's made. On another card, the bake's card keeps all its memory for the simulation, and the simulation never waits for the mesh. Surface On shows on any computer with an NVIDIA card.
Cards
Cards lets a big liquid or smoke be solved over several cards at once, each holding its part, so bigger ones fit:
| Choice | Solves a liquid or smoke |
|---|---|
| Auto | Over every usable card, when it's big: about 130,000 particles, or 256 blocks of smoke, a card and up. Smaller ones stay on the bake's card |
| This GPU | On the bake's card alone |
| Pick | Over the cards ticked below, with the bake's |
The result is the same to the bit however many cards share it.
Other kinds of particles (plain particles, rigid bodies) stay on the bake's card. While a simulation is spread over several cards, background bakes wait for those cards to be free.