Single CPU Server vs Dual CPU Server: What's the Difference?

The Center Process Unit (CPU) used on the server is the server CPU. The main function of server CPU is to process data, instructions, and perform operations. As an important network device, servers can achieve fast throughput of large data volume, super stability, and long-term operation with a better server CPU.

Generally speaking, according to the number of physical CPUs, servers can be divided into one-way, two-way, four-way and eight-way servers. This article will mainly focus on single and dual CPU servers.

What Is Single CPU Server?

As the name implies, a single CPU server refers to a single-socket server with only one CPU socket on the motherboard, that is, only one CPU is running. Therefore, compared to multiprocessor servers, a single CPU server has lower consumption, fewer requirements for cooling system, and also less hardware costs.

What's more, a single CPU server also features with cost effectiveness, since as the number of cores increases, so does the cost. And the software licenses are also cheaper. But single CPU servers don't have enough RAM capacity, which is its major downside.

What Is Dual CPU Server?

Dual CPU servers, also called dual processor servers, have two CPU sockets on the motherboard. With two CPUs working at the same time, dual CPU servers are real servers to some extent. To be clear, different from dual-core servers, which install two CPU cores on one CPU, dual processor has two CPU card slots on the motherboard.

Typically, dual CPU servers perform better than single CPU servers in terms of performance and stability. However, they are more expensive too.

Single CPU Server vs Dual CPU Server

As two basic server types, single CPU servers are often compared with dual CPU servers in some respects, such as server RAM, performance, use case, etc.

Performance

In most cases, servers with more CPUs outperform single CPU servers, because dual CPU servers come with a large number of PCI lanes, two independent sets of cache, and two sets of RAM slots, which are all associated with increased performance. Besides, since dual processor servers work with two CPU threads, they perform at higher rates than single-processor servers that use a single thread.

However, according to some tests, dual CPU servers perform slightly better than single CPU servers with similar core-count and clock speeds per chip, especially when both CPUs are processing the same data simultaneously. Most of the time, dual CPU servers will greatly boost their performance when the workload is optimized, especially when CPU is performing intensive multithreaded tasks. That's because they can abstract resources into virtual machines.

Therefore, dual CPU servers are the best choice for space-constrained environments due to their higher stability and performance.

Use Case

Under different circumstances, the use cases of two kinds of servers are also of variety.

• Single CPU servers: Advances in CPU technology have enabled single processor servers to handle intensive workloads. A low-end single CPU server can be very cost-effective to build general-purpose application servers for smaller organizations. Besides, single CPU servers can be used for medium capacity online stores or large websites, working as collaborative servers for smooth data exchange between different departments.

• Dual CPU servers: Equipped with great processor chips, dual CPU servers are suitable for almost every business use case. But in most situations, they are chosen by large enterprises for high-end computing applications. Due to their better performance and stability, dual processor servers can provide more computing power and are usually used for scientific high-precision computing and simulations, high-performance computing (HPC) deployment, etc.

Server RAM

Single CPU servers are different from dual CPU servers in terms of server RAM. Typically, dual CPU servers have more RAM capacity than single CPU servers. But single CPU servers are more flexible when it comes to choosing RAMs.

On the Intel platform, single processor servers support ECC or non-ECC memory. However, dual processor servers only support FB－DIMM ECC memory. Besides, on AMD platform, single CPU servers support ECC, non-ECC, and Registered ECC RAM, but dual CPU servers only support Registered ECC RAM.

Conclusion

In conclusion, although single CPU servers are cheaper, they are still incomparable to dual CPU servers in terms of performance and stability. Companies should make suitable choices based on their requirements and the use cases of servers.