220-1101 Question 258
Single answerMotherboard form factorsA technician is upgrading a small office desktop that uses a damaged microATX motherboard inside a standard mid-tower ATX case. The existing power supply is functioning properly, and the company wants the lowest-cost replacement that will fit the case without changing the power supply or leaving the system unable to mount correctly. Which motherboard form factor should the technician choose?
- A
ATX
- B
MicroATX
- C
Mini-ITX
- D
BTX
Show answer and explanation
Correct answer: B
Explanation
The best answer is MicroATX because motherboard replacement should prioritize physical compatibility with the case, mounting points, rear I/O alignment, and power connections. In the ATX family, microATX is a common and cost-effective replacement choice for systems originally built with microATX boards. A standard ATX case typically supports smaller boards such as microATX, but replacing a board with the same form factor reduces the chance of fitment issues and preserves expected expansion and header placement. CompTIA A+ Core 1 expects candidates to understand common motherboard form factors such as ATX, microATX, and Mini-ITX, along with practical compatibility considerations. Industry best practice is to verify case support, standoff alignment, rear I/O shield fit, and PSU connector compatibility before installation.
- A. Incorrect.
ATX is incorrect for this scenario because, although an ATX board often fits in a standard mid-tower ATX case, it is larger than microATX and may not match the existing mounting point layout or feature requirements of the original system. It also is not typically the lowest-cost like-for-like replacement when replacing a damaged microATX board. Choosing a larger board can introduce unnecessary compatibility and cost considerations.
- B. Correct.
MicroATX is correct because it matches the original motherboard form factor and is designed to fit in both microATX and many standard ATX cases. It typically uses the same standard ATX-family power connectors in modern desktop systems, making it the most practical and lowest-cost replacement without requiring case or power supply changes.
- C. Incorrect.
Mini-ITX is incorrect because, while it is smaller and can often mount in compatible ATX cases, it may not provide the same expansion slot capacity or front-panel/header layout expected in a business desktop. It is also not usually the most direct replacement for an existing microATX office system and can complicate reuse of existing expansion hardware.
- D. Incorrect.
BTX is incorrect because BTX was a different motherboard and case layout standard and is not interchangeable with standard ATX/microATX mounting and airflow designs. A BTX motherboard generally requires a BTX-compatible case, so it would not be an appropriate drop-in replacement in a standard ATX mid-tower case.