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# maxTransferRate

The highest theoretical rate, in bytes per second, the system can copy between system memory and the GPU’s dedicated memory (VRAM).

```
var maxTransferRate: UInt64 { get }
```

## Discussion

Metal calculates this value from the raw data-clock rate, and the GPU may not be able to reach this speed in real-world conditions.

> Important:
> The maximum transfer rate for built-in GPUs is `0`.

---

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