Thecorrect and safemethod to remove the backplane from the motherboard tray is to useboth hands, gently tilting thetop of the backplanetowards yourself while carefullylifting it up and outof the motherboard tray.

This ensures that:

No undue forceis applied to the connectors or PCB.

No components or cablesare unintentionally damaged.

Proper handling of static-sensitive componentsis maintained.

Removing the backplane improperly can result in:

Connector damageto the motherboard or backplane.

PCB warping, which could lead to future malfunctions.

Potential data center downtimedue to component failure.

According toSupermicro's official documentation, this method aligns withindustry best practicesandrecommended service proceduresforSupermicro MI300X GPU systems.

InSupermicro MI300X GPU systems, theNVMe backplane is located behind the motherboard tray, meaning the tray must be removed first.

Why is this step necessary?

The NVMe backplane is physically secured behind the motherboard trayto support high-speed PCIe connectivity.

Removing the motherboard tray provides clear accessto NVMe connectors and MCIO cables.

Skipping this step may cause unnecessary strain on cables, leading to potential connector damage.

Official Documentation Reference:

Supermicro Service Guide for NVMe Systemsconfirms that themotherboard tray must be removed firstbefore working on the NVMe backplane.

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.

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.

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.

Why Must the Motherboard Tray Be Removed First?

TheNVMe backplane in Supermicro MI300X systemsis installedbehind the motherboard tray. This means themotherboard tray acts as a barrier, andit must be removed before gaining access to the NVMe backplane.

Step-by-Step Removal Process:

Power Down and Disconnect Power Supply Units (PSUs)

Turn off the system anddisconnect all power cablesto avoid electrical damage.

Remove PCIe Expansion Cards(if applicable)

Some systems have PCIe devicesmounted over the NVMe backplane, which must be removed first.

Disengage the Motherboard Tray

The motherboard tray must be unscrewed and carefully lifted outbefore accessing the NVMe backplane.

Now, Remove the NVMe Backplane

Once the motherboard tray is out, theNVMe backplane is fully exposed, allowing it to be removed.

Why Other Options Are Incorrect?

A (GPU Tray)→ The GPU tray isnot blocking direct accessto the NVMe backplane.

C (Power Supply Unit)→ The PSU isnot directly obstructingthe NVMe backplane, although it should be powered down.

D (PCIe Expansion Cards)→ These may need to be removedif installed over the NVMe backplane, but themotherboard tray is the primary component that blocks direct access.

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Installation Guideexplicitly states thatthe motherboard tray must be removed before handling the NVMe backplane.

Why Secure One End of the PCIe Tray First?

TheSupermicro MI300X chassis is designed for modular tray installation, meaningsecuring one end firstensures:

Proper alignment of PCIe slots and connectors

Stable mountingto prevent unwanted movement

Prevention of unnecessary strain on installed expansion cards

What Happens If Both Ends Are Handled at the Same Time?

ThePCIe tray may shift out of alignment, making it difficult to properly install other components.

Misalignment can cause:

PCIe devices to not seat properly

Power or data cables to be obstructed

Increased risk of mechanical damage during reinstallation

Step-by-Step Correct Installation Process:

✅Step 1:Align the PCIe tray with its designated mounting slots.✅Step 2:Secure screws onone end firstto hold the tray in place.✅Step 3:Adjust the other end and ensureproper seatingbefore fully tightening all screws.✅Step 4:Reconnect all PCIe cables and verify system connectivity.

Why Other Options Are Incorrect?

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

C (Tray will not function)→ The tray will functiononce properly seated, butincorrect installation can lead to PCIe misalignment.

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

Official Documentation Reference:

Supermicro AS-8125GS-TNMR2 Service Guideconfirms thattrays must be secured at one end first to ensure proper alignment.

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) bracketis used to mount optional components like:

RAID controllers

Additional networking interfaces

BMC/IPMI modules

In theexample system shown in the video, theright AOM bracket does not contain an AOM card. This is because:

Supermicro’s default system configurations do not always ship with optional AOM cards.

Theleft AOM bracketusually housesoptional RAID or networking expansions, but theright bracket remains unoccupiedunless a specific expansion module is installed.

Official Documentation Reference:

SupermicroHardware Deployment Guideconfirms that theright AOM bracket is optionalandnot pre-installedin base configurations.