CompTIA A+: Lesson 3 (Starting from CPU)

1. What are the four basic operations performed by the CPU on each instruction?

• Fetch: Retrieves the instruction from memory.

• Decode: Determines what the instruction means.

• Execute: Carries out the instruction.

• Store: Saves the result.

• ECC memory support.

What is the difference between ARM (RISC) and x86/x64 (CISC)?

• RISC (ARM): Uses a simpler instruction set, often allowing better power efficiency.

• CISC (x86/x64): Uses a more complex instruction set, commonly found in desktop PCs and servers.

What is Simultaneous Multithreading (SMT)?

Allows one physical CPU core to handle multiple threads at the same time, improving overall CPU utilisation.

• Intel calls its version Hyper-Threading.

• AMD calls its version SMT.

What is the difference between LGA and PGA CPU sockets?

• LGA (Land Grid Array): Pins are located in the motherboard socket.

• PGA (Pin Grid Array): Pins are located on the CPU itself.

The CPU and motherboard must have compatible sockets to fit and operate correctly.

5. What are Intel Core i3/i5/i7/i9 and AMD Ryzen 3/5/7/9 processors?

These are processor performance tiers:

Tier	Typical use
i3 / Ryzen 3	Basic office tasks
i5 / Ryzen 5	Everyday multitasking
i7 / Ryzen 7	Gaming and demanding workloads
i9 / Ryzen 9	High-performance workloads

What are server-class CPUs such as Intel Xeon and AMD EPYC designed for?

They are designed for servers and data centres, offering features such as:

• Support for large amounts of RAM.

• ECC memory support.

• High core counts.

• Reliability and stability for continuous operation.