Starting today, Amazon RDS Custom for SQL Server supports memory-optimized X2iedn instance types and EBS-optimized R5b instance types. Amazon RDS Custom for SQL Server is a managed database service that allows customization of the underlying operating system and includes the ability to bring your own licensed SQL Server media or use SQL Server Developer Edition.

X2iedn instances are powered by 3rd generation Intel Xeon Scalable Processors (Ice Lake). X2iedn instances are designed for the requirements of high performance enterprise-class databases, by offering high compute (up to 128 vCPUs), large memory (up to 4 TB) and storage throughput (up to 256K IOPS) with a 32:1 memory to vCPU ratio. 

R5b instance types, powered by the AWS Nitro System, are well-suited for relational database workloads requiring high EBS bandwidth, delivering up to 60 gigabytes per second of EBS-optimized bandwidth and 64K IOPS with SQL Server. R5b instances allow Amazon RDS customers to migrate workloads to smaller-sized R5b instances and still meet their workload IOPS requirements, saving on compute and licensing costs. 

You can learn about using X2iedn instances with local storage to maximize TempDB performance by reading this blog. See Amazon RDS Custom for SQL Server Pricing for up-to-date pricing of instances, storage, data transfer and regional availability.