SMI300XS Supermicro MI300X GPU Service Specialist (SMI300XS) Exam Questions and Answers

When servicing theSupermicro MI300X GPU system, there are3 screwssecuring thebracket at the bottom of the motherboard trayin front of the backplane.

Purpose of these screws:

They secure the backplane’s structural integrityto prevent vibration-related failures.

Loosening them allows the removal or replacement of backplane componentssafely.

They prevent accidental disconnectionscaused by handling or system movement.

Why other options are incorrect?

A (13 screws)→ This number istoo highfor just the bottom bracket.

B (21 screws) & C (30 screws)→ These numbersapply to entire system disassembly, not just the bottom bracket.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Disassembly Guidespecifies thatonly 3 screwsneed to be loosened to access thebottom bracket securing the backplane.

Themidplane in Supermicro MI300X GPU systemsis responsible for interconnecting several system components. The twoprimary cablesthat must be removed before handling themidplaneare:

I2C Cable (Inter-Integrated Circuit Cable)

This cable is used forsensor data, system monitoring, and thermal control.

If not disconnected, it couldsnap or cause sensor miscommunicationbetween the motherboard and the backplane.

Power Cable

This cablesupplies powerto the midplane andmust be disconnected before removalto avoid electrical damage.

Removing the midplanewhile power cables are still attachedcould short-circuit the system.

Why is this step necessary?

Supermicro's official documentation states that both the I2C and power cables must be disconnected before handling the midplane.

Failure to remove these cables properly can cause permanent damage to connectors and the system board.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Maintenance Manualconfirms thatdisconnecting the I2C and power cables is mandatory before midplane removal.

When reinstalling theNVMe backplane, several critical cables must be properlyreconnectedto ensure the system functions correctly.

Required Connections:

SATA Cable→ Some NVMe backplanesalso support SATA drives, requiring SATA connectivity.

Power Cables→ The NVMe backplanerequires direct powerto enable SSD operations.

MCIO Cables→ These cables providehigh-speed data connectivitybetween the NVMe drives and the motherboard.

54-Volt Power Cable→ Thissupplies direct powerto the NVMe backplane foroptimal performance and stability.

Why other options are incorrect?

B (Only SATA cable)→ NVMe backplanes usePCIe-based storage. While SATA connectionsmayexist,they are not the only required cables.

C (Only MCIO cables)→ While MCIO cables are necessary for PCIe-based NVMe drives,power cables must also be reconnectedfor the system to function.

D (Only power cables)→Data communication would failwithout MCIO connections, rendering the systemunable to detect NVMe drives.

Official Documentation Reference:

Supermicro NVMe Service GuideandAS-8125GS-TNMR2 Installation Manualemphasize thecorrect reinstallation of power and data cablesto avoidhardware malfunctions.

Why Must the Motherboard Tray Be Aligned With the Grooves?

TheSupermicro MI300X chassisis designed withbuilt-in alignment groovesthat helpprecisely position the motherboard tray.

If the tray is notaligned properly:

ThePCIe slots and mounting points will not line up correctly.

Thebackplane connections may be misaligned, leading to system boot errors.

Improper installation can block airflow, leading to potential overheating issues.

Step-by-Step Proper Reinstallation Process:

✅Step 1:Identify thealignment grooveson the chassis.✅Step 2:Slowly slide the motherboard tray into place, ensuring it follows the grooves.✅Step 3:Verify that the tray sitsflushwith the chassis.✅Step 4:Secure the tray with screws only after confirming proper alignment.

Why Other Options Are Incorrect?

B (Shake the tray to confirm fit)→ Shaking the traycan loosen connectors and potentially damage components.

C (Screw in randomly before aligning)→ If screws are installedbefore alignment, it can causeuneven seating and difficulty in securing other components.

D (Tilt the motherboard tray at an angle)→ The tray should be insertedstraight into the grooves, not at an angle.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Installation Guideconfirms thatthe motherboard tray must be aligned with the chassis grooves before securing it.

Removing the motherboardrequires careful handlingto preventbending pins, PCB damage, or static discharge.

Correct Removal Process:

First, remove all 12 screws securing the motherboard.

Avoid touching any exposed pins or contacts.

Carefully slide the motherboard slightly out of the rear of the tray.

Support it with one hand underneath to prevent bending.

Continue sliding it out without tilting it.

Why other options are incorrect?

A (Touch pins & shove motherboard)→ Touching pins cancause electrostatic damageandforcing it out can damage components.

B (Hold like a pizza)→ Usingone handdoes not provide enough support, increasing the risk ofbending or dropping the motherboard.

C (Tilt chassis & shake it out)→ This is acompletely impropermethod and canseriously damageconnectors and PCB components.

Official Documentation Reference:

Supermicro MI300X System Removal Guideadvises toslide the motherboard out carefully while supporting it underneath.

ForSupermicro MI300X GPU systems,removing the power supply unit (PSU) improperlycan lead to serious issues.

Why the red lock exists?

Thered locking mechanismensures that thePSU is properly securedin the system.

Before disengaging the PSU, thered lock must first be unlockedto avoid damage.

If you forcefully shift the release lever without unlocking the red lock:

B: The power supply unit will fail→ If the PSU is removed improperly, it can causeinternal damageto power connectors, resulting in PSUfailure or improper functioning.

C: You could permanently damage the lock on the power supply unit→ Thelocking mechanismis designed for smooth disengagement. Forcefully shifting the lever canbreak or warpthe lock, making itimpossible to secure the PSU back in place.

Incorrect Answers Explained:

A (All answers are correct)→ This is incorrect becausenot all answers are valid.

D (The PSU can no longer be secured into the tray)→ This happensonly if the lock is damaged, which is covered underoption C.

Supermicro’s official documentation clearly statesthatunlocking the red lock firstis a critical step before removing or replacing the PSU.

Why Do Supermicro Systems Use Grooves for Alignment?

InSupermicro MI300X systems, themidplane bracket is aligned using built-in grooves in the chassis.

Ensures Perfect Alignment

The midplane mustline up perfectlywith power, PCIe, and data connections.

Grooves act as physical guides, ensuringprecise placementwithout guesswork.

Prevents Installation Errors

Without grooves, technicians mightinstall the midplane slightly misaligned, leading toconnection failures.

Ensures PCIe and MCIO lanes align correctly, preventing signal loss.

Supports a Tool-Free Installation

Grooves allowdrop-in installation, reducingmanual adjustments.

Minimizes risk of flexing or damaging the midplane PCB.

Why Other Options Are Incorrect?

A (Guide stickers in the chassis)→ Stickersmay be present for labeling but do not physically align the midplane.

C (Arrows in the chassis)→ Arrows arevisual indicators only, not physical alignment tools.

D (Velcro in the chassis)→ Velcro isnot used in midplane installation.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Hardware Guideexplicitly states thatgrooves in the chassis help with midplane bracket alignment.

The SKU (Stock Keeping Unit) forSupermicro NVMe backplanesvaries depending on thespecific model and system configuration.

Thecorrect SKU for the NVMe backplane used in the Supermicro MI300X system differs from the given part number.

Referencingofficial Supermicro product sheets and service manuals, theBPN-NVME5-HS219N-S24 does not matchthe correct SKU for this system.

Official Documentation Reference:

Supermicro NVMe Storage System Compatibility Guidelists the correct SKU for MI300X GPU systems, confirming that the given SKU is incorrect.

Themidplane bracket in Supermicro MI300X GPU systemsis secured with6 screwsthat must beremoved before disassembly.

Why 6 screws?

3 screws on each side of the chassishold the midplane bracket in place.

This design helps stabilize the midplaneand prevents movement.

Failure to remove all 6 screws can result in forcefully damaging the bracket.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Disassembly Manualspecifies that6 screws must be removed before handling the midplane bracket.