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

Thepower cableis the only cable that isnot a data cablewhen connecting an AOM card to the motherboard.

Cable Functionality Breakdown:

A (Power Cable) → NOT a data cable

Supplies electrical powerto the AOM card.

Doesnot transmit databetween components.

B (MCIO Cables) → Data cables

These cablestransmit high-speed NVMe data.

C (JNCIS1) → Data cable

This interface is used formanagement and communication.

D (SAS Cable) → Data cable

Used fordata storage connections.

Official Documentation Reference:

Supermicro AOM Expansion Module Guidestates that thepower cable is the only non-data cablein AOM installations.

Components Located on Top of the Motherboard in Supermicro MI300X Systems

Fans and Fan Shrouds (Option A)

These are installedabove the motherboardtodirect airflow over the components.

Fan shrouds help focus airflow, ensuringefficient cooling of CPUs and GPUs.

Support Bar and AOM Brackets (Option B)

Thesupport bar reinforces the motherboard tray, preventing flexing.

AOM bracketshold optionalnetworking or RAID expansion modules.

Heatsinks and CPUs (Option C)

Large heatsinks are mounted on top of the CPUsto dissipate heat.

These ensureoptimal thermal managementof high-performanceAMD MI300X GPUs and processors.

Why Option D (DIMM Modules) is Incorrect?

❌DIMM modules (memory sticks) are installed in slots beside the CPU, but they arenot physically above the motherboardin a way that they could be considered a top-mounted component.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 System Overviewconfirms thatfans, heatsinks, AOM brackets, and support bars are mounted on top of the motherboard.

TheAOM (Add-On Module) cardis a crucial expansion module used inSupermicro MI300X GPU systemsfor enhanced connectivity (e.g., RAID controllers, additional network interfaces, or IPMI management).

What happens if AOM cables are misplaced?

The AOM card may not function

The system depends onspecific cabling configurationsto communicate with the AOM module.

Incorrect connections can causehardware failures, incorrect detection, or data transmission errors.

PCIe lane allocation may be disrupted

Many AOM cards usePCIe lanesfor data transmission.Misplacing cables can disable or limit their bandwidth, leading to performance degradation.

BIOS may not detect the AOM card

Some AOM cards requirefirmware initialization, which only happens if the correct ports are used.

Incorrect Answers Explained:

A (System will self-destruct)→ The systemwill not explode, butit may fail to boot properly.

B (Customer will be happy)→ Misconfigured AOM cards typically lead tosystem errors and dissatisfied customers.

D (System will function normally)→ If cables are misplaced,the system will not function properly.

Official Documentation Reference:

Supermicro MI300X GPU System Hardware Guidestates thatAOM cables must be reconnected in their proper ports for the system to function correctly.

Removing themidplanein aSupermicro MI300X GPU systemrequiresdisengaging multiple system trays and power componentsbeforehand.

Why is this necessary?

Power must be fully disengaged before midplane removal

The midplane is directly connected topower distribution units (PDUs).

If power is not removed, it can causeshort circuits or hardware damage.

PCIe, motherboard, and GPU trays block access

These trays must be disengagedbefore removing the midplane, as they contain components directly connected to it.

Dummy PSUs must also be removed

Even inactive PSUs containlocking mechanismsthat must be disengaged.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 System Removal Guideconfirms thatPSUs, dummy PSUs, PCIe trays, motherboard trays, and GPU trays must be removed before handling the midplane.

When reinstalling trays (GPU, motherboard, or PCIe) inSupermicro MI300X GPU systems, it iscrucial to secure one end firstbefore working on the opposite end.

Why is this necessary?

To prevent tray misalignment

Trays in Supermicro systemshave specific guide rails and screwsthat must bealigned correctly before full installation.

If both ends are handled simultaneously,one end may shift, causingmounting misalignment.

Avoiding unwanted movement

If you install a tray at both ends without securing one first,it can get pushed out, leading to incorrect seating.

This can causepoor PCIe connectivity, power delivery issues, or misaligned airflow paths.

Ensuring cables are properly routed

If a tray is not secured properly,cables may shift during installation, increasing the risk of pinched or damaged cables.

Why other options are incorrect?

B (Cables getting in the way)→ While cable management is important, the key issue istray movement, not cables.

C (Tray will not function)→ The traywill function once properly seated, but incorrect installation cancause connectivity issues.

D (Tray will break)→ The tray is designed for durability;it will not break unless excessive force is applied.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Service Guideconfirms that traysmust be secured at one end before installing the opposite end to ensure proper 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.

Understanding the AOM Bracket in Supermicro MI300X Systems

TheAOM (Add-On Module) bracketis used to holdoptional expansion cards, such as:

RAID controllers

Additional network interface cards (NICs)

BMC/IPMI modules for system management

Why is the Screw Located on the Side of the Motherboard Tray?

The AOM bracket is secured to the chassis via a single screwthat is located on theside of the motherboard tray.

This designkeeps the bracket firmly in placewhile still allowing foreasy removal when needed.

Removing the screw first prevents unnecessary strain on the bracketand ensuressafe removal of the AOM card.

Why Other Options Are Incorrect?

A (On top of the hard drive tray)→ The hard drive tray does not secure the AOM bracket.

B (On top of the fan tray)→ Fans do not hold down the AOM bracket.

D (On the rear of the power supply)→ The power supplyis not directly connected to the AOM bracket.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Expansion Module Guidespecifies that theAOM bracket is secured by a single screw located on the side of the motherboard tray.

Why is the Purple 5V Power Connector Critical?

InSupermicro MI300X systems, thepurple 5V power connectorisresponsible for delivering stable low-voltage powerto specific components.

Consequences of Incorrect Power Connector Placement:

????1. System Failure or Non-Booting State

If the5V power connector is plugged into the wrong port, the systemmay not receive proper voltage, leading to failure.

⚡2. Component Damage

Overvoltage or incorrect voltage levelsmayfry sensitive system components(e.g., NVMe controllers, PCIe devices).

????3. Risk of Short Circuit

Plugging the power cable into an incorrect portmay cause short circuits, leading topermanent hardware damage.

Proper Connection Steps:

✅Step 1:Identify thepurple 5V connectoron the PSU and NVMe backplane.✅Step 2:Match it with the correct5V porton the system board.✅Step 3:Ensure asecure and firm connectionbefore powering the system back on.

Why is False Incorrect?

IfFalse were correct, it would imply thatincorrectly plugging the power connector has no consequences, which iswrong.

Supermicroexplicitly warns against incorrect power connectionsdue topotential damage risks.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Electrical Guidestates thatincorrect power connections can lead to irreversible hardware failure.

Understanding MCIO Cables in Supermicro MI300X Systems

MCIO (Multi-lane Cable I/O) connectorsare used forhigh-speed data transmission between the motherboard and NVMe SSDs or PCIe devices.

These connectorsmust be handled carefully, as improper removal cancause pin damageorpermanent failure of the interface.

How to Properly Unlock and Release MCIO Cables

Locate the release levers on the MCIO connectors

Each MCIO connector has asmall built-in release leverthat locks it in place.

Press down on the release levers

This disengages the locking mechanism andallows the cable to slide out easily.

Gently pull the MCIO cable straight out

Do not pull at an angleas it can damage thehigh-density connector pins.

Why Other Options Are Incorrect?

A (Pull really hard)→ Forcing the connector without releasing the latch canbreak the MCIO pins or damage the motherboard socket.

B (Remove screws)→ MCIO cablesdo not use screws; they have built-in locking mechanisms.

D (Loosen bolts)→ There areno boltssecuring MCIO cables; only therelease lever is needed for unlocking.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Motherboard Manualstates thatpressing down on the release levers is the correct method to unlock MCIO cables.