Explanation
This is because the HPE ProLiant DL560 Gen10 server is a 2U rack server that supports up to four Intel Xeon Scalable processors with up to 48 cores per processor. It also supports up to 6 TB of memory and up to 12 LFF or 24 SFF drives.1 It can satisfy the customer requirements of having two processors and scaling to four inside a 2U chassis.

Core Boosting technology uses a relaxed and optimized turbo profile that adapts the processor to specific use cases, configurations, and environments. Core Boosting processors take advantage of extra server power and thermal headroom provided by an innovative HPE voltage regulator design and by cooling technologies.
Consequently, systems that have Core Boosting processors can alleviate common setbacks and maximize processor computing power.
However, Core Boosting option is only supported in ProLiant Gen10 servers with certain Intel processors1. The HPE ProLiant DL380 Gen10 server data sheet2 lists the supported processors for Core Boosting as:
Intel Xeon Gold 6148 Processor (20 core, 2.4 GHz, 27.5 MB L3 cache)
Intel Xeon Gold 6154 Processor (18 core, 3.0 GHz, 24.75 MB L3 cache)
Intel Xeon Gold 6152 Processor (22 core, 2.1 GHz, 30.25 MB L3 cache)
Intel Xeon Platinum 8168 Processor (24 core, 2.7 GHz, 33 MB L3 cache)
Therefore, if your customer's DL380 Gen10 servers are running workloads on more active cores at higher clock frequencies, they can benefit from Core Boosting technology if they have one of these supported Intel processors.

ML Series: The HPE ProLiant ML series servers are designed as tower servers, making them ideal for small offices. They offer the necessary performance and scalability for File & Print workloads while being easy to manage and deploy in a small office environment.
Reference:
HPE ProLiant ML Series

Data deduplication is a technique used to reduce storage requirements by identifying and eliminating duplicate data. HPE SimpliVity features data deduplication as a key benefit, which can result in significant cost savings and improved storage efficiency.

According to IBM, a SAN is a dedicated network that provides access to consolidated, block-level data storage
1. A SAN allows multiple servers to access shared pools of storage devices, such as disk arrays or tape libraries1. A SAN can help your customer consolidate data and add additional block-based storage to their main document management application.