EC2 C7a instances land in AWS US West (N. California)
Amazon's AMD EPYC Genoa-powered compute instances are now available in a fourth US region, bringing higher memory bandwidth and expanded EBS attachment limits.
Are EC2 C7a instances available in US West (N. California)?
Yes, as of July 22, 2026, Amazon has expanded EC2 C7a instance availability to the US West (N. California) Region. The compute-optimized instances run on 4th Gen AMD EPYC (Genoa) processors and are built on the AWS Nitro System, making them suitable for workloads where raw CPU throughput and memory bandwidth matter.
What does C7a offer over C6a?
The headline improvement is a claimed performance uplift of up to 50% compared to the previous C6a generation. That gain comes from a combination of the newer processor architecture running at up to 3.7 GHz maximum frequency and DDR5 memory, which the announcement says delivers 2.25 times more memory bandwidth than DDR4-based C6a instances.
The C7a generation also adds processor instruction set extensions that were absent on C6a: AVX-512, VNNI (Vector Neural Network Instructions), and bfloat16. Those additions are relevant for teams running inference workloads, signal processing, or any code that can be compiled to take advantage of wider SIMD operations.
EBS attachment limits get a major increase
One less-publicized change is worth noting for storage-heavy architectures. C7a instances support attaching up to 128 EBS volumes to a single EC2 instance. C6a instances cap out at 28 EBS volume attachments, so the jump is substantial for workloads that aggregate many volumes, such as distributed databases or analytics clusters.
Instance sizes and purchase options
| Attribute | C7a | C6a |
|---|---|---|
| Processor | 4th Gen AMD EPYC (Genoa) | 3rd Gen AMD EPYC (Milan) |
| Max frequency | 3.7 GHz | Not specified in source |
| Memory type | DDR5 | DDR4 |
| Memory bandwidth vs. prior gen | 2.25× more than C6a | Baseline |
| Performance vs. prior gen | Up to 50% higher | Baseline |
| Available sizes | 12 (medium to 48xlarge + bare metal) | Not specified in source |
| Max EBS volume attachments | 128 | 28 |
C7a comes in 12 sizes, spanning from medium up to 48xlarge, with a bare-metal option for workloads that need direct hardware access without a hypervisor layer. Instances are available on On-Demand, Spot, and Savings Plans pricing models.
Recommended workloads
Amazon positions C7a for compute-intensive tasks: batch processing, distributed analytics, high performance computing, ad serving, large-scale multiplayer gaming, and video encoding. The DDR5 memory bandwidth improvement also makes the instances a reasonable fit for latency-sensitive applications that spend significant time waiting on memory reads.
How to get started
The instances can be provisioned through the AWS Management Console, the AWS CLI, or any of the AWS SDKs. Teams currently running workloads on C6a in N. California now have a direct migration path within the same region rather than needing to cross to US East or other geographies to access the C7a generation.