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CompTIA A+

Chapter 1

Safety and Professionalism -

Xx

Chapter 2

Visible Computer -

Xx

Chapter 3

CPU Processors -

Microarchitecture -

Is the underlying digital logic that allows an instruction set to be executed. It is the combined implementation of registers, memory, arithmetic logic units, multiplexers, and any other digital lock blocks. All of it, together, forms the processor

APU -

Built in graphics CPU's are called APU, designed to act as a central processing unit (CPU) and graphics processing unit (GPU) on a single die.

Clock Speeds -

Also known as clock rates the speed in which a microprocessor can execute commands, an internal clock regulates the rate at which instructions are executed and synchronizes all the various computer components.

Megahertz MHZ

Gigahertz GHZ

Chapter 4

RAM - Random Access Memory

RAM

Memory is one of the most important parts on your PC, it is constantly communicating back and forth with the CPU. Short term memory between the CPU and the Hard drives.

DIMM - Dual inline Memory Module -

DIMMs have a 64-bit data width which gives it the capability to transfer data from these memory modules in 64-bit data blocks at a time.

SODIMM - Small outline Inline Memory Module

Used for mobile devices, laptops and tablets.

Micro DIMM - Small Form Factor Memory

Also made for mobile devices

DRAM - Dynamic Random Access Memory -

In DRAM, “random” means that information in memory can be accessed anytime in the memory module at any place. Data is not retrieved in a sequential process, it can be retrieved randomly. An address of data is used to get the data.

DRAM is asynchronous. This was a problem with gathering data as it comes in so it can be queued for the process it was working with. Due to DRAM being asynchronous, it was not going to work as fast with processors that were just getting faster.

SDRAM- Synchronous Dynamic Random Access Memory -

SDRAM is a type of DRAM that is synchronized with the processor system bus for a speed advantage. Since SDRAM is synchronous, and therefore relies on a clock to synchronize signals, creating predictable orderly cycles of data fetches and writes. SDRAM transfers data on one edge of the clock.

- RAM Parity vs. Non-Parity -

Parity checking is a method of detecting memory errors, without any correction capabilities. Every byte has a “parity” bit associated with it, for a total of 9 bits per byte (8 data bits plus one parity bit)

The parity bit is set at write time and then calculated and compared at read time to determine if any of the bits have changed since the data was stored. This type of checking is limited to detection of single bit errors

- ECC vs. Non-ECC -

Error Correction Code (ECC) is similar to parity, but more advanced. It can detect multiple errors in data returned from memory and actually correct a single error. ECC memory has 89 extra bits to support the ECC. The system board used must support ECC and all of the memory in the system must be ECC for ite to be actively supported. - ECC or non-parity RAM - Count the number of chips on one side. If it is even it is non-ECC. If it is uneven it is ECC.

Chapter 5

Firmware -

POST- Power On Self-Test

The Power On Self-Test takes place every time a system starts.

The CPU checks the motherboard and verifies that the peripherals and other hardware connected to the motherboard are working order.

If hardware is not detected error may display or beep code to notify the user

however, because of the wide variety of different computers manufacturers with this BIOS, the beep codes may vary.

POST Card-

A card use to test a desktop or a PC to check what parts may be having issues

Hexadecimal code generated pointing to the issue the code would be indicated in vendors manufacturer.

Legacy BIOS - Basic Input Output System

BIOS contains POST, Boot loaders and initialize it.

Located on the motherboard

RTC - Real Time Clock

A real-time clock is a computer clock that keeps track of the current time.

CMOS -

Older version of the BIOS chip could not be upgraded and would lose saved settings if the battery was dead or taken out newer UEFI BIOS CMOS only control date and time.

Solutions -

CMOS jump -

Clearing the motherboard BIOS take out the motherboards battery for 10 minutes

CR2032 Battery -

Batteries for motherboard holds the time of system and used by some services.

UEFI BIOS- Unified Extensible Firmware Interface

New version of BIOS has a few advantages to its counterpart

Based on Intel’s EFI (Extensible Firmware Interface) - Can boot from drives of 2.2TB or larger

New Tools UEFI

1.

Secure Boot - Checks validity to the OS ensure no malware has tampered with the boot.

Cryptographically secure

2.

Pre Boot Environment - has a virtual environment where you can browse the web, remote diagnostic without an OS

3.

Saves changes into flash memory rather than the CMOS chip.

Flashing BIOS -

Flashing the ROM updates the firmware on the flash chip

ROM -

Reflash able chips that can be upgraded in their firmware

Hard Drive Encryption -

Bit Locker - encrypts the entire hard drive.

Lojack Laptops

Tracking device built in firmware of the motherboard enable regardless of hard drives.

Location - tracking

Theft Mode - Remote lock/wipe

Forced Start up - Forces a password change

TPM - Trust platform Module -

Specialize chip on device that contains the encryption RSA keys on the local unit for authentication.

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