CompTIA A+ 220-901 Review | 2026/2027 | Official Practice Test 1
COMPTIA A+ 220-901 REVIEW OFFICIAL
PRACTICE TEST 1
2026/2027 | 90 Questions with Correct Answers | Hardware & Networking Fundamentals
Graded A+ | 100% Verified | Evidence-Based Rationales
Instructions
This examination consists of 90 multiple-choice questions covering the five core domains of the retired CompTIA A+
220-901 exam: PC Hardware and Components, Networking Fundamentals, Mobile Devices and Laptops, Virtualization
and Cloud Concepts, and Hardware and Network Troubleshooting with Operational Procedures. The recommended
time limit is 90 minutes. This practice test emphasizes the CompTIA 6-Step Troubleshooting Methodology, which is
heavily tested on both the 220-901 and current 220-1201/1202 exams. Be prepared for Performance-Based Questions
(PBQs) on the actual exam that require hands-on configuration and diagnostic skills. Correct answers are displayed in
bold cyan with evidence-based rationales aligned to CompTIA A+ exam objectives, TIA/EIA standards, IEEE 802
standards, and manufacturer specifications.
Select the single best answer for each question. Each question is worth one point. A score of 675/900 (approximately
75%) is the passing threshold for the actual CompTIA A+ exam. Use this practice test to identify knowledge gaps and
guide further study.
Section I: PC Hardware and Components
1. Which motherboard form factor measures 12 inches by 9.6 inches and provides the most expansion slots among
standard consumer form factors?
A. Mini-ITX
B. microATX
C. ATX
D. FlexATX
Rationale: The ATX (Advanced Technology eXtended) form factor, standardized by Intel in 1995, measures 12 x
9.6 inches and provides up to seven expansion slots. Per CompTIA A+ 220-901 objectives, ATX is the most
common full-size desktop form factor. Mini-ITX measures 6.7 x 6.7 inches with a single expansion slot, and
microATX measures 9.6 x 9.6 inches with up to four expansion slots.
2. A technician is replacing a CMOS battery on a motherboard. What is the primary purpose of this battery?
A. Powers the CPU during peak load conditions
B. Maintains BIOS/UEFI settings and the real-time clock when the system is powered off
C. Provides backup power for RAM during sleep mode
D. Supplies voltage to the PCIe slots
Rationale: The CMOS (Complementary Metal-Oxide-Semiconductor) battery, typically a CR2032 lithium coin
cell, maintains BIOS/UEFI configuration settings, the system real-time clock (RTC), and stored hardware
parameters when the PC is powered off. Per CompTIA A+ exam objectives, if the CMOS battery fails, the system
1
, CompTIA A+ 220-901 Review | 2026/2027 | Official Practice Test 1
will lose its boot configuration and display a CMOS checksum error on POST. This is covered under the 1.1
objective for motherboards.
3. When connecting front panel connectors to a motherboard, which of the following is true regarding pin polarity
for the power LED?
A. Pin polarity does not matter for any front panel connector
B. The positive (+) pin must connect to the anode lead of the power LED for it to illuminate
C. The power LED connector only uses a single pin
D. Front panel connectors use USB polarity standards
Rationale: Unlike the power switch and reset switch connectors (which are non-polarized), the power LED and
HDD LED are polarized. The positive (+) pin must connect to the colored wire (typically green for power LED),
and the negative (-) pin connects to the black or white ground wire. Reversing the polarity will prevent the LED
from illuminating. Per CompTIA A+ 220-901 objectives under motherboard connectors, technicians must
understand front panel header pin configurations.
4. A computer emits a single long beep followed by two short beeps during POST. According to standard AMI
BIOS beep codes, what component should the technician investigate?
A. RAM failure
B. Video adapter / graphics card failure
C. CPU overheating
D. Keyboard error
Rationale: Standard AMI BIOS beep codes indicate a video adapter error with one long beep followed by two
short beeps. This POST (Power-On Self-Test) diagnostic helps identify hardware failures before the OS loads.
Per CompTIA A+ 220-901 objectives under POST and beep codes, technicians must memorize common beep
code patterns. A single long repeated beep indicates RAM failure, while a repeating short beep indicates power
supply or motherboard issues.
5. Which CPU socket type uses a Land Grid Array (LGA) package where the pins are located on the motherboard
socket rather than on the processor itself?
A. Socket AM4
B. Socket FM2
C. LGA 1151
D. Socket G34
Rationale: LGA (Land Grid Array) sockets place the contact pins on the motherboard socket itself, while the
CPU has flat contact pads. LGA 1151 is used for Intel 6th through 9th generation Core processors. Per CompTIA
A+ 220-901 objectives, CPU sockets are categorized as LGA (Intel), PGA (Pin Grid Array, e.g., AMD AM4), and
BGA (Ball Grid Array, soldered directly to the motherboard). PGA sockets have pins on the CPU that insert into
holes on the motherboard.
6. A technician is applying thermal compound between a CPU and its heat sink. Which statement describes the
correct application method?
A. Apply a thick layer covering the entire CPU surface for maximum cooling
B. Apply a pea-sized amount in the center and allow the heat sink pressure to spread it evenly
C. Apply thermal compound to both the CPU and the heat sink surfaces
D. Thermal compound is not needed if using a liquid cooling system
2
, CompTIA A+ 220-901 Review | 2026/2027 | Official Practice Test 1
Rationale: The correct thermal compound application method is a pea-sized dot (approximately 3–5mm) in the
center of the CPU integrated heat spreader (IHS). Heat sink mounting pressure spreads the compound into a thin,
even layer. Per CompTIA A+ 220-901 objectives under cooling methods, too much thermal compound can act as
an insulator and reduce cooling efficiency. Thermal paste IS required even with liquid cooling systems, between
the CPU and the cold plate.
7. What does TDP (Thermal Design Power) specify for a CPU?
A. The maximum overclocking frequency achievable
B. The maximum amount of heat generated by the CPU that the cooling system must dissipate,
measured in watts
C. The total data throughput of the CPU in gigabytes per second
D. The minimum voltage required for stable CPU operation
Rationale: TDP (Thermal Design Power) measures the maximum amount of heat a CPU generates under normal
workload that the cooling system must be able to dissipate, expressed in watts. Per CompTIA A+ 220-901
objectives under CPUs, TDP helps technicians select appropriate cooling solutions. A CPU with a 95W TDP
requires a more robust cooling solution than one rated at 65W. TDP is not the actual power consumption but a
design metric for thermal management.
8. A customer wants to upgrade their laptop RAM. Which type of memory module is specifically designed for use
in laptops and compact devices?
A. DIMM (Dual Inline Memory Module)
B. SO-DIMM (Small Outline DIMM)
C. SIMM (Single Inline Memory Module)
D. RIMM (Rambus Inline Memory Module)
Rationale: SO-DIMM (Small Outline Dual Inline Memory Module) is the memory form factor designed
specifically for laptops and compact devices. SO-DIMMs are approximately 67% the size of standard desktop
DIMMs. Per CompTIA A+ 220-901 objectives under RAM types, DDR3 SO-DIMMs have 204 pins and DDR4
SO-DIMMs have 260 pins, compared to 240 and 288 pins respectively for full-size desktop DIMMs.
9. Which type of RAM includes an extra parity bit for error detection and is commonly used in servers and
mission-critical applications?
A. DDR4 Non-ECC
B. ECC (Error-Correcting Code) RAM
C. Registered DIMM without ECC
D. DDR3 SO-DIMM
Rationale: ECC (Error-Correcting Code) RAM includes additional memory bits and logic to detect and correct
single-bit memory errors. It is commonly used in servers, workstations, and mission-critical applications where
data integrity is paramount. Per CompTIA A+ 220-901 objectives, ECC memory requires a motherboard and
CPU that support ECC functionality. Desktop CPUs and motherboards typically do not support ECC RAM, while
server-grade hardware does.
10. A system has DDR4 RAM installed. To achieve dual-channel memory operation, which of the following is
required?
A. Install a single DDR4 module in slot 0
B. Install two identical DDR4 modules in the correct paired slots (e.g., slots 0 and 2 or 1 and 3)
C. Install four identical DDR4 modules in all available slots
3
COMPTIA A+ 220-901 REVIEW OFFICIAL
PRACTICE TEST 1
2026/2027 | 90 Questions with Correct Answers | Hardware & Networking Fundamentals
Graded A+ | 100% Verified | Evidence-Based Rationales
Instructions
This examination consists of 90 multiple-choice questions covering the five core domains of the retired CompTIA A+
220-901 exam: PC Hardware and Components, Networking Fundamentals, Mobile Devices and Laptops, Virtualization
and Cloud Concepts, and Hardware and Network Troubleshooting with Operational Procedures. The recommended
time limit is 90 minutes. This practice test emphasizes the CompTIA 6-Step Troubleshooting Methodology, which is
heavily tested on both the 220-901 and current 220-1201/1202 exams. Be prepared for Performance-Based Questions
(PBQs) on the actual exam that require hands-on configuration and diagnostic skills. Correct answers are displayed in
bold cyan with evidence-based rationales aligned to CompTIA A+ exam objectives, TIA/EIA standards, IEEE 802
standards, and manufacturer specifications.
Select the single best answer for each question. Each question is worth one point. A score of 675/900 (approximately
75%) is the passing threshold for the actual CompTIA A+ exam. Use this practice test to identify knowledge gaps and
guide further study.
Section I: PC Hardware and Components
1. Which motherboard form factor measures 12 inches by 9.6 inches and provides the most expansion slots among
standard consumer form factors?
A. Mini-ITX
B. microATX
C. ATX
D. FlexATX
Rationale: The ATX (Advanced Technology eXtended) form factor, standardized by Intel in 1995, measures 12 x
9.6 inches and provides up to seven expansion slots. Per CompTIA A+ 220-901 objectives, ATX is the most
common full-size desktop form factor. Mini-ITX measures 6.7 x 6.7 inches with a single expansion slot, and
microATX measures 9.6 x 9.6 inches with up to four expansion slots.
2. A technician is replacing a CMOS battery on a motherboard. What is the primary purpose of this battery?
A. Powers the CPU during peak load conditions
B. Maintains BIOS/UEFI settings and the real-time clock when the system is powered off
C. Provides backup power for RAM during sleep mode
D. Supplies voltage to the PCIe slots
Rationale: The CMOS (Complementary Metal-Oxide-Semiconductor) battery, typically a CR2032 lithium coin
cell, maintains BIOS/UEFI configuration settings, the system real-time clock (RTC), and stored hardware
parameters when the PC is powered off. Per CompTIA A+ exam objectives, if the CMOS battery fails, the system
1
, CompTIA A+ 220-901 Review | 2026/2027 | Official Practice Test 1
will lose its boot configuration and display a CMOS checksum error on POST. This is covered under the 1.1
objective for motherboards.
3. When connecting front panel connectors to a motherboard, which of the following is true regarding pin polarity
for the power LED?
A. Pin polarity does not matter for any front panel connector
B. The positive (+) pin must connect to the anode lead of the power LED for it to illuminate
C. The power LED connector only uses a single pin
D. Front panel connectors use USB polarity standards
Rationale: Unlike the power switch and reset switch connectors (which are non-polarized), the power LED and
HDD LED are polarized. The positive (+) pin must connect to the colored wire (typically green for power LED),
and the negative (-) pin connects to the black or white ground wire. Reversing the polarity will prevent the LED
from illuminating. Per CompTIA A+ 220-901 objectives under motherboard connectors, technicians must
understand front panel header pin configurations.
4. A computer emits a single long beep followed by two short beeps during POST. According to standard AMI
BIOS beep codes, what component should the technician investigate?
A. RAM failure
B. Video adapter / graphics card failure
C. CPU overheating
D. Keyboard error
Rationale: Standard AMI BIOS beep codes indicate a video adapter error with one long beep followed by two
short beeps. This POST (Power-On Self-Test) diagnostic helps identify hardware failures before the OS loads.
Per CompTIA A+ 220-901 objectives under POST and beep codes, technicians must memorize common beep
code patterns. A single long repeated beep indicates RAM failure, while a repeating short beep indicates power
supply or motherboard issues.
5. Which CPU socket type uses a Land Grid Array (LGA) package where the pins are located on the motherboard
socket rather than on the processor itself?
A. Socket AM4
B. Socket FM2
C. LGA 1151
D. Socket G34
Rationale: LGA (Land Grid Array) sockets place the contact pins on the motherboard socket itself, while the
CPU has flat contact pads. LGA 1151 is used for Intel 6th through 9th generation Core processors. Per CompTIA
A+ 220-901 objectives, CPU sockets are categorized as LGA (Intel), PGA (Pin Grid Array, e.g., AMD AM4), and
BGA (Ball Grid Array, soldered directly to the motherboard). PGA sockets have pins on the CPU that insert into
holes on the motherboard.
6. A technician is applying thermal compound between a CPU and its heat sink. Which statement describes the
correct application method?
A. Apply a thick layer covering the entire CPU surface for maximum cooling
B. Apply a pea-sized amount in the center and allow the heat sink pressure to spread it evenly
C. Apply thermal compound to both the CPU and the heat sink surfaces
D. Thermal compound is not needed if using a liquid cooling system
2
, CompTIA A+ 220-901 Review | 2026/2027 | Official Practice Test 1
Rationale: The correct thermal compound application method is a pea-sized dot (approximately 3–5mm) in the
center of the CPU integrated heat spreader (IHS). Heat sink mounting pressure spreads the compound into a thin,
even layer. Per CompTIA A+ 220-901 objectives under cooling methods, too much thermal compound can act as
an insulator and reduce cooling efficiency. Thermal paste IS required even with liquid cooling systems, between
the CPU and the cold plate.
7. What does TDP (Thermal Design Power) specify for a CPU?
A. The maximum overclocking frequency achievable
B. The maximum amount of heat generated by the CPU that the cooling system must dissipate,
measured in watts
C. The total data throughput of the CPU in gigabytes per second
D. The minimum voltage required for stable CPU operation
Rationale: TDP (Thermal Design Power) measures the maximum amount of heat a CPU generates under normal
workload that the cooling system must be able to dissipate, expressed in watts. Per CompTIA A+ 220-901
objectives under CPUs, TDP helps technicians select appropriate cooling solutions. A CPU with a 95W TDP
requires a more robust cooling solution than one rated at 65W. TDP is not the actual power consumption but a
design metric for thermal management.
8. A customer wants to upgrade their laptop RAM. Which type of memory module is specifically designed for use
in laptops and compact devices?
A. DIMM (Dual Inline Memory Module)
B. SO-DIMM (Small Outline DIMM)
C. SIMM (Single Inline Memory Module)
D. RIMM (Rambus Inline Memory Module)
Rationale: SO-DIMM (Small Outline Dual Inline Memory Module) is the memory form factor designed
specifically for laptops and compact devices. SO-DIMMs are approximately 67% the size of standard desktop
DIMMs. Per CompTIA A+ 220-901 objectives under RAM types, DDR3 SO-DIMMs have 204 pins and DDR4
SO-DIMMs have 260 pins, compared to 240 and 288 pins respectively for full-size desktop DIMMs.
9. Which type of RAM includes an extra parity bit for error detection and is commonly used in servers and
mission-critical applications?
A. DDR4 Non-ECC
B. ECC (Error-Correcting Code) RAM
C. Registered DIMM without ECC
D. DDR3 SO-DIMM
Rationale: ECC (Error-Correcting Code) RAM includes additional memory bits and logic to detect and correct
single-bit memory errors. It is commonly used in servers, workstations, and mission-critical applications where
data integrity is paramount. Per CompTIA A+ 220-901 objectives, ECC memory requires a motherboard and
CPU that support ECC functionality. Desktop CPUs and motherboards typically do not support ECC RAM, while
server-grade hardware does.
10. A system has DDR4 RAM installed. To achieve dual-channel memory operation, which of the following is
required?
A. Install a single DDR4 module in slot 0
B. Install two identical DDR4 modules in the correct paired slots (e.g., slots 0 and 2 or 1 and 3)
C. Install four identical DDR4 modules in all available slots
3
