Generally available: The A4 accelerator-optimized machine type is now generally available

## Feature **Generally available**: The [A4 accelerator-optimized machine type](https://cloud.google.com/compute/docs/accelerator-optimized-machines#a4-vms) is now generally available. A4 instances are powered by NVIDIA B200 GPUs and provide up to 3x performance of previous GPU instance types for most GPU accelerated workloads. A4 is especially recommended for ML training workloads at large scales. A4 is available in the `a4-highgpu-8g` machine type in the `us-central1-b` zone. To create A4 instances, you must either use AI Hypercomputer to request capacity and create VMs or clusters, or use Spot VMs. For detailed instructions, see [Create an A3 Ultra or A4 VM](http://cloud.google.com/compute/docs/gpus/create-gpu-vm-a3u-a4).