CompTIA A+ Core 1 and Core 2
120 flashcards by MentisLibrary
Hardware, mobile devices, networking, virtualization and cloud, operating systems, security, software troubleshooting and operational procedures, with the ports, specs and commands the A+ Core 1 and Core 2 exams expect.
- What are the A+ Core 1 and Core 2 domains?
- Core 1 covers mobile devices, networking, hardware, virtualization and cloud computing, and hardware and network troubleshooting. Core 2 covers operating systems, security, software troubleshooting and operational procedures.
- The six steps of the CompTIA troubleshooting methodology
- Identify the problem, establish a theory of probable cause, test the theory to determine the cause, establish a plan of action and implement the solution, verify full system functionality and apply preventive measures, then document findings, actions and outcomes.
- ATX, microATX and Mini-ITX board sizes
- ATX is 12 by 9.6 inches (305 by 244 mm), microATX is 9.6 by 9.6 inches (244 by 244 mm) and Mini-ITX is 6.7 by 6.7 inches (170 by 170 mm). A case built for a larger form factor accepts the smaller boards.
- How many pins does a DDR4 DIMM have?
- 288, the same count as DDR5, but the notch sits in a different place so the two will not seat in each other's slots. DDR3 uses 240 pins.
- What is dual channel memory?
- Two matched modules in the paired slots so the memory controller reads from both at once, roughly doubling bandwidth. Boards mark the pairs with slot color or labels such as A1, B1, A2, B2.
- ECC memory
- Error correcting code memory carries an extra chip that detects and corrects single-bit errors in flight. It requires CPU and motherboard support and belongs in servers and workstations, not typical desktops.
- SATA data and power connector pin counts
- The data connector has 7 pins and the power connector has 15. SATA revision 3 runs at 6 Gb/s, which is roughly 600 MB/s of usable throughput.
- M.2 SATA versus M.2 NVMe
- M.2 is a slot form factor, not a protocol. The module inside speaks either SATA at 6 Gb/s or NVMe over PCIe lanes at several GB/s, and the key notch tells you which.
- RAID 0
- Striping across two or more disks. Reads and writes split across the members for speed and you keep the full combined capacity, but there is no redundancy at all.
- RAID 1
- Mirroring: every write lands on both disks, so the array survives one failure and you get the usable capacity of a single disk.
- RAID 5
- Striping with parity distributed across three or more disks. It survives one disk failure and gives up the capacity of one disk to parity.
- RAID 6
- Striping with two independent parity blocks across four or more disks. It survives two simultaneous failures at the cost of two disks of capacity.
- RAID 10
- A stripe of mirrors: two or more mirrored pairs striped together, minimum four disks. It gives mirror-level rebuild speed with stripe-level performance and half the raw capacity.
- ATX power connectors on a modern build
- A 24-pin main connector for the board, a 4+4-pin EPS12V connector for the CPU, 6-pin or 8-pin PCIe connectors for the graphics card, and 15-pin SATA connectors for drives.
- Rails a PC power supply provides
- +3.3 V, +5 V and +12 V for the system, plus a -12 V rail for legacy serial circuitry and a +5 V standby rail that keeps the board alive while the machine is off.
- LGA versus PGA CPU sockets
- In a land grid array the pins live in the socket and the CPU has flat contact pads. In a pin grid array the pins are on the CPU. Intel desktop parts are LGA, and AMD moved from PGA on AM4 to LGA on AM5.
- Why does a CPU need thermal paste?
- It fills the microscopic gaps between the processor lid and the cooler base so heat actually transfers. A pea-sized amount spreads under clamping pressure.
- What does a CPU's TDP tell you?
- Thermal design power, the heat in watts the cooling solution must remove at sustained load. It sizes the cooler.
- USB data rates by generation
- USB 2.0 is 480 Mb/s, USB 3.2 Gen 1 is 5 Gb/s, USB 3.2 Gen 2 is 10 Gb/s, USB 3.2 Gen 2x2 is 20 Gb/s and USB4 reaches 40 Gb/s.
- Thunderbolt 3 and Thunderbolt 4
- 40 Gb/s over a USB-C connector, carrying PCIe and DisplayPort at the same time, with daisy chaining of up to six devices.
- DisplayPort versus HDMI
- Both carry digital video and audio. DisplayPort uses a latching connector and can drive several monitors from one port through Multi-Stream Transport; HDMI is the television standard and carries CEC device control.
- The laser printing process in order
- Processing, charging, exposing, developing, transferring, fusing and cleaning.
- How do you clean up spilled toner?
- Use a vacuum with a toner-rated HEPA filter, and wash toner off skin or clothing with cold water.
- Impact printer maintenance
- Replace the ribbon, replace the print head and replace the paper. Impact printers strike through a ribbon, so they are the only type that prints multipart carbon forms.
- Thermal printer maintenance
- Replace the thermal paper, clean the heating element with isopropyl alcohol and remove any paper debris.
- Inkjet printer maintenance
- Clean the print heads, calibrate, clear jams and replace cartridges. A cleaning cycle clears a clogged nozzle.
- Hard drive form factors and rotational speeds
- 3.5 inch drives go in desktops and 2.5 inch drives in laptops and servers. Consumer spindle speeds are 5400 and 7200 RPM, with 10000 and 15000 RPM on enterprise SAS drives.
- PCIe slot sizes and lane counts
- PCIe slots come as x1, x4, x8 and x16, where the number is the lane count. A shorter card works in a longer slot, and a longer card fits an open-ended shorter slot at reduced bandwidth.
- Digitizer versus display panel
- The digitizer is the touch-sensing layer that reports finger position; the panel is the LCD or OLED that shows the image.
- Where do laptop Wi-Fi antennas run?
- Up the sides of the display lid, so they sit high and away from the metal chassis.