220-1101 - Hardware (25% of the exam) - Section 3.2

Install RAM and storage devices, including DDR generations, ECC and non-ECC, SSD form factors, and RAID levels in a given scenario.

Select and install the correct RAM - matching DDR3, DDR4, or DDR5 to the motherboard, choosing DIMM for desktops and SODIMM for laptops, and recognising when ECC or registered modules are required for servers. Distinguish storage device form factors and interfaces (2.5-inch SATA, M.2 SATA versus M.2 NVMe, mSATA) and identify the redundancy and performance trade-offs of RAID 0, 1, 5, and 10.

DDR4 and DDR5DIMM vs SODIMMM.2 NVMeRAID levels

Practice question for this objective

Free sampleHardwarehard

Priya is upgrading a desktop built on a motherboard with DDR5 DIMM slots. She has a spare 16 GB DDR4 UDIMM from an older PC and tries to seat it, but it will not lock into the slot. What is the correct next step?

AApply firm and even pressure until the retention clips finally engage the DDR4 module in the slot.
BUpdate the motherboard BIOS so the DDR5 slot will accept and train the DDR4 module.
CObtain a DDR5 DIMM, because DDR4 and DDR5 place their keying notch in different positions and are not interchangeable. Correct
DFile down the DDR4 module's notch so that it aligns with the DDR5 slot's key.

DDR generations are physically and electrically incompatible; a DDR5 slot only accepts a DDR5 module, not an older DDR4 one. JEDEC positions the keying notch differently on each DDR generation precisely to stop a wrong-generation module seating. DDR4 and DDR5 also differ in voltage and pin count, so the only valid fix is to fit a genuine DDR5 DIMM rather than force, flash, or file the DDR4 module.

Why A is wrong: Tempting because stiff new slots do need firm seating, but forcing a mis-keyed module risks cracking the board or slot and the notch mismatch means it will never seat.

Why B is wrong: A BIOS update can add compatibility for same-generation kits, but no firmware makes a physically different DDR4 notch fit a DDR5 slot.

Why C is correct: Correct: the notch sits at a different point on each generation, so a DDR4 module cannot seat in a DDR5 slot and a matching DDR5 DIMM is required.

Why D is wrong: Reshaping the key seems to solve the fit, but the generations differ in voltage and pinout too, so a modified module would still not work and would be ruined.

See more 220-1101 practice questions, answers explained.

Exam traps in Hardware

Answers that look right on this material and are not. Each one is a distractor from a different question in the 220-1101 bank for this domain.

It is a SODIMM with 288 pins, matching the desktop DDR4 DIMM pin count in a shorter package.
Why it is wrong: SODIMM is the right laptop form factor, but a DDR4 SODIMM has 260 pins, not 288, so the pin figure is wrong.
A SATA III 2.5-inch SSD connected to the free SATA port.
Why it is wrong: SATA III SSDs boot quickly, but the interface caps near 6 Gbps, about 550 MB/s, well below what the PCIe socket allows.
ATX and microATX use identical board dimensions and differ only in the CPU socket family they accept.
Why it is wrong: Tempting because both share the ATX power and mounting standard, but the two form factors have different maximum board sizes, so this is wrong.

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