# GPU FAQs

**Q1. What types of GPU configurations are supported in PCD?**

PCD supports three modes:

* **GPU Passthrough** – Full GPU assigned to a VM
* **vGPU** – Fractional GPU assigned using vendor-defined profiles

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**Q2. Can a host support both Passthrough and vGPU on the same GPU?**

No. A physical GPU can only operate in **one mode at a time**—either Passthrough or vGPU. <code class="expression">space.vars.product\_acronym</code> blocks conflicting configurations during setup.

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**Q3. What if the host has multiple GPUs?**

You can configure each GPU on the host independently. Currently, we do not support a combination of multiple GPU modes on a single host. For example, all GPUs on a host can be passthrough or vGPU.

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**Q4. Can I change the GPU mode of a cluster on VMs are already running?**

No. You must ensure no VM is using the GPU before changing its mode. The system will prevent mode changes if the GPU is actively assigned.

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**Q5. What are vGPU profiles and who defines them?**

vGPU profiles are predefined by NVIDIA. Each profile determines how much GPU memory and what capabilities are given to a VM (e.g., `Nvidia-35`, `Nvidia-40`). Only one profile type can be used per GPU at a time.

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**Q6. How are GPU-enabled VMs scheduled to GPU hosts?**

GPU-enabled flavors are mapped to GPU-capable host. <code class="expression">space.vars.product\_acronym</code> schedules VMs only to hosts with compatible GPU hardware and profiles.

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**Q7. Can I migrate a VM with a GPU?**

* **Passthrough GPU:** Live migration is allowed only if the destination host has the same specific physical GPU hardware available.
* **vGPU:** Live migration is allowed **only if** the destination host supports the same GPU profile and model.

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**Q8. How do I know how much GPU memory is available?**

<code class="expression">space.vars.product\_acronym</code> will display GPU resource availability per host or per host aggregate, including free VRAM. This helps admins plan capacity and allocations.

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**Q9. How do I know what GPU model is on a host?**

GPU Host details in the console will list GPU model, mode (Passthrough/vGPU), available profiles, and current usage.

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**Q10. Can I add a non-GPU host to a GPU cluster?**

No, Currently, <code class="expression">space.vars.product\_acronym</code> does not support it.

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**Q11. Can we passthrough two GPU cards to single VM?**

Yes, you can passthrough two or more GPU cards to single VM by configuring GPU flavor.

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**Q12: Does pausing or suspending a GPU VM automatically release underlying GPUs and re-attach on resuming/power on?**

Currently the GPU are not released and reattached to new GPU VM automatically.

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**Q13: Is VM HA supported for GPU-enabled clusters?**

No, VM HA is currently not supported for GPU-enabled clusters.

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**Q14: Can we over provision GPU passthrough physical PCI resources?**

No, you can not over provision the physical GPU PCI passthrough hardware, unlike CPU,Memory over provision ratios.

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