3.4 - Motherboards, RAID and cooling
CompTIA A+ Core 1 objective 3.4 covers motherboards, RAID arrays and cooling. RAID 5 provides striping with parity and can survive the loss of a single drive, needing at least three disks. RAID 10 combines mirroring and striping, needs a minimum of four drives, and offers both redundancy and speed. On the motherboard, a modern dedicated graphics card uses the PCIe x16 slot. For cooling, thermal paste between a CPU and its heatsink improves heat transfer to the cooler, and must be reapplied when a heatsink is removed. Expect scenario questions that describe a fault-tolerance requirement, an expansion slot choice or a cooling task and ask which RAID level, slot or step is correct. Count the minimum drives to tell them apart: three for RAID 5, four for RAID 10.
Striping + parity, survives 1 drive (min 3) = RAID 5. Mirror + stripe (min 4) = RAID 10. Modern GPU slot = PCIe x16. CPU-to-heatsink heat transfer = thermal paste.
Practice questions
1. A high-TDP CPU needs the best sustained cooling. Which solution is BEST?
- A passive heatsink with no fan
- A closed-loop liquid (AIO) cooler (correct answer)
- A single case fan on its own
- Running with the side panel removed
A closed-loop liquid (AIO) cooler dissipates high heat loads better than basic air for high-TDP CPUs.
2. Which RAID level provides striping with parity and can survive the loss of a single drive?
- RAID 0
- RAID 1
- RAID 5 (correct answer)
- RAID 10
RAID 5 stripes data with distributed parity across 3+ drives and tolerates one drive failure. RAID 0 has no redundancy; RAID 1 mirrors.
3. What is the purpose of thermal paste between a CPU and its heatsink?
- Glue the heatsink permanently
- Insulate the CPU electrically
- Improve heat transfer to the cooler (correct answer)
- Prevent static discharge
Thermal paste fills microscopic air gaps so heat moves efficiently from the CPU die to the heatsink.
4. Which expansion slot is used for a modern dedicated graphics card?
- The PCIe x1 slot
- The PCIe x16 slot (correct answer)
- The M.2 slot
- The SATA port
GPUs use the full-length PCIe x16 slot for maximum bandwidth. x1 is for small cards; M.2/SATA are storage.
5. Which RAID level requires a minimum of four drives and provides BOTH mirroring and striping?
- RAID 0
- RAID 5
- RAID 10 (correct answer)
- RAID 1
RAID 10 (1+0) mirrors pairs then stripes across them, needing at least four drives, combining redundancy and speed.
6. Which motherboard form factor is the SMALLEST of these and common in compact PCs?
- ATX
- microATX
- Mini-ITX (correct answer)
- Extended ATX
Mini-ITX (170x170 mm) is the smallest common form factor. ATX is full-size; microATX is in between.