The processors AMD EPYC 9645 are a very powerful and efficient option for web servers, especially those requiring high processing capacity and handling large volumes of requests. They belong to AMD's EPYC 9005 series, specifically designed for high-performance server environments.

Here are its key features and why they are suitable for web servers:

• Cores and Threads: The EPYC 9645 features 96 CPU cores and 192 threads. This large core count allows the server to handle multiple tasks and requests concurrently, which is crucial for high-traffic web environments where numerous requests are processed simultaneously.
• Clock Speed: Operates at a base frequency of 2.3 GHz, and can reach a turbo frequency of up to 3.7 GHz, adjusting to the workload. This ensures the processor can respond quickly to both routine tasks and peak demands.
• L3 Cache: It incorporates a generous 256 MB L3 cache. A large cache is crucial for server performance, as it reduces the time the processor takes to access frequently used data, speeding up database operations and content delivery.
• Memory: Supports 12-channel DDR5 memory, with speeds up to 6400 MT/s. DDR5 compatibility and a high number of memory channels mean significantly higher memory bandwidth, which is vital for memory-intensive applications like large databases or caching services.
• PCI Express Connectivity: It features 128 PCI Express 5.0 (PCIe 5.0) lanes. PCIe 5.0 offers double the bandwidth of PCIe 4.0, allowing extremely fast communication with other server components, such as high-speed NVMe storage drives or 100 GbE network cards and above, reducing data transfer bottlenecks.
• Manufacturing Technology: It is manufactured using a 3nm process. A smaller manufacturing process generally translates to higher energy efficiency and better performance per watt, which is beneficial for reducing operational costs in data centers.

Advantages for Web Servers:

• Efficient Multitasking: The large number of cores and threads allows the web server to handle a large number of client connections, execute PHP processes, database queries, and other web server tasks without slowdowns.
• Database Performance: The combination of high speed, large L3 cache, and support for 12-channel DDR5 memory directly benefits databases (like MariaDB 11.4.4, which you mentioned), accelerating data read and write operations.
• Scalability: With 192 threads, these processors are well-positioned to scale and handle the growth of traffic and the complexity of web applications.
• Energy Efficiency: The 3nm technology contributes to lower power consumption relative to performance, which can result in lower cooling and electricity costs in a data center.
• High Connectivity: PCIe 5.0 connectivity is ideal for servers utilizing high-speed NVMe storage for databases or caching systems, and for high-speed networking handling large traffic volumes.

There are already companies offering VPS (Virtual Private Server) lines based on the AMD EPYC 9645, highlighting its performance.

In summary, the AMD EPYC 9645 is a high-end processor that offers exceptional performance in terms of processing power, memory management, and I/O connectivity, making it a very solid choice for web servers looking to maximize efficiency and responsiveness, especially for high-traffic WordPress sites or demanding web applications.