S Grade Circuit Board Scrap: Identification, Examples and Boundaries

S Grade Circuit Board Scrap Classification | Ohata Board Classification Wiki

What Qualifies as S Grade Circuit Board Scrap?

S Grade is Ohata's premium board-scrap category below SS Grade and above A+ Grade. It is intended for selected legacy computer and storage boards, especially non-SATA HDD controllers and older server boards with three or more large purple ceramic CPUs, dense integrated circuits, substantial gold connectors and intact multilayer construction. Do not assign S Grade from one feature or a manufacturer name. Gold fingers alone are insufficient. Telecom switching, optical transport, cellular base-station and network-backbone boards should first be checked against the SS Grade criteria.

S Grade is a premium category within the Ohata Board Classification system within the Ohata Board Classification, positioned below SS Grade and above A+ Grade within the Ohata Board Classification system. It refers to selected high-value printed circuit boards (PCBs) that typically include non-SATA HDD controller boards and selected legacy computer boards with high concentrations of precious-metal-bearing electronic components and are commonly recovered from enterprise, industrial, telecommunications, scientific, and high-end computing equipment.

Within the Ohata Board Classification, the term S Grade is an internal public classification used exclusively for identifying purchasing categories of electronic circuit boards. It is not an industry standard, government specification, or electronics manufacturing grade.

The purpose of the classification is to establish a consistent identification method for buyers, recyclers, dismantlers, collectors, and sellers of electronic scrap.

Unlike traditional descriptions such as "high grade board" or "telecom board," the S Grade category follows defined identification principles rather than relying only on appearance or market perception.

Purpose of the S Grade Classification

Electronic scrap contains thousands of different PCB designs.

Many boards appear similar while containing completely different material values.

For example:

• two telecom boards may have completely different precious metal contents

• two server boards may have different component densities

• one military board may contain gold-plated connectors while another contains very little recoverable precious metal

Without board classification, purchasing decisions become inconsistent.

The Ohata Board Classification establishes a common identification language.

The objectives include:

• consistent purchasing guideline

• improved visual identification

• inspection procedures

• easier staff training

• clearer public education

• better communication between buyers and sellers

Why Some Boards Are Classified as S Grade

The classification is based on observable physical characteristics rather than laboratory assay.

Typical characteristics include:

• extremely high component density

• multiple large integrated circuits

• numerous ceramic IC packages

• heavy gold-plated edge connectors

• dense arrays of tantalum capacitors

• gold-plated pin connectors

• multilayer PCB construction

• premium manufacturing quality

• specialized industrial applications

A board does not become S Grade because of one feature alone.

Instead, inspectors evaluate the overall construction and electronic complexity.

Typical Equipment Producing S Grade Boards

Examples include:

• HDD Non-SATA Board

• enterprise servers

• telecommunications switches

• network backbone equipment

• industrial automation systems

• scientific instruments

• medical imaging equipment

• data center hardware

• optical communication systems

• legacy mainframe computers

• storage controllers

• RAID systems

• high-end workstation hardware

Not every board from these products qualifies as S Grade.

Each board is individually inspected.

Characteristics of S Grade Boards

Typical visual features include:

High IC Density

Large numbers of integrated circuits covering significant PCB area.

Gold Edge Connectors

Heavy gold fingers are frequently present.

Gold Pin Arrays

Multiple gold-plated connectors may be installed.

High Layer Count

Many S Grade boards are manufactured using multilayer PCB technology.

Name the visible component

ceramic CPU package, BGA controller, memory array or gold connector.

High-performance electronics generally require expensive components.

Difference Between Electronic Grade and Scrap Grade

Engineering grade refers to manufacturing specifications.

Scrap classification refers to purchasing identification.

These are entirely different concepts.

The Ohata Board Classification does not evaluate:

• electrical performance

• reliability

• manufacturing quality

• engineering certification

It only classifies boards for purchasing identification.

Scope of This Wiki

This page explains:

• identification

• characteristics

• common board types

• recycling considerations

• purchasing classification

• environmental importance

• visual inspection methods

It does not provide precious metal assay values or guaranteed purchasing prices.

How to Identify an S Grade Board

Correct identification begins with visual inspection.

Several characteristics are evaluated together.

Step 1 — Examine Overall Component Density

High-density boards generally contain:

• processors

• controllers

• memory chips

• ASICs

• FPGA devices

• communication ICs

Dense layouts usually indicate sophisticated electronic design.

Step 2 — Inspect Gold Connectors

Gold-plated edge connectors are common.

Inspect:

• connector length

• plating condition

• number of connector edges

• connector thickness

Gold fingers alone do not guarantee S Grade.

Step 3 — Count Large IC Packages

Enterprise boards often contain:

• BGA processors

• ceramic processors

• network ASICs

• switch controllers

• storage processors

The number and distribution of ICs are considered.

Step 4 — Identify Ceramic Components

Older enterprise equipment frequently includes ceramic IC packages.

These may appear as:

• white ceramic

• black ceramic

• gold-lidded ceramic

• pin-grid ceramic

These components often increase classification importance.

Step 5 — Evaluate Connectors

Inspect:

• backplane connectors

• telecom connectors

• DIN connectors

• gold pin headers

• edge connectors

Large industrial connectors are common.

Step 6 — Examine PCB Construction

Premium boards often include:

• thick PCB substrate

• multiple copper layers

• precision solder mask

• reinforced mounting areas

Step 7 — Look for Industrial Manufacturing Features

Examples:

• conformal coating

• military labeling

• revision tracking

• serial identification

• quality inspection labels

Common S Grade Examples

Common HDD Non-SATA (IDE/PATA, ATA, EIDE, SCSI) hard drive manufacturers include:

• Seagate

• Western Digital (WD)

• Hitachi

• IBM

• Toshiba

• Fujitsu

• Samsung

• Maxtor

• Quantum

• Conner Peripherals

• Micropolis

• Miniscribe

• Rodime

• NEC

• ExcelStor

• JTS (JTS Corporation)

• Quantum Fireball Series

• IBM Deskstar Series

• Hitachi Travelstar Series

• Fujitsu MPE/MHT Series

Typical candidates include:

• Cisco telecom boards

• Nortel switching boards

• Lucent telecom boards

• Alcatel communication boards

• IBM server processor boards

• HP enterprise controllers

• EMC storage boards

• RAID controller assemblies

• Sun Microsystems server boards

• Oracle enterprise hardware

• industrial PLC CPU boards

• scientific instrument controller boards

Inspection is always performed individually.

Boards Often Mistaken for S Grade

Examples include:

• desktop motherboards

• laptop motherboards

• television boards

• DVD player boards

• appliance control boards

• printer boards

Although valuable, many belong to different purchasing categories.

Visual Inspection Checklist

Inspect:

✔ IC quantity

✔ connector plating

✔ board complexity

✔ PCB thickness

✔ application

✔ overall density

Classification is based on the complete board rather than one feature.

Recycling Value and Material Characteristics

S Grade boards are recognized because they generally contain large quantities of advanced electronic components.

However, recycling value depends on many factors.

Precious Metals

Electronic boards may contain:

• gold

• silver

• palladium

These metals are primarily found in:

• connector plating

• IC bonding wires

• component terminations

• contact surfaces

Actual recoverable quantities vary considerably.

Base Metals

Boards also contain:

• copper

• tin

• nickel

• aluminum

• steel

Copper represents one of the largest recoverable materials.

Why Enterprise Boards Are Valuable

S Grade enterprise boards are valuable because they contain dense integrated circuits, ceramic CPUs, high-quality connectors, multilayer PCBs, and higher concentrations of recoverable gold, copper, silver, and palladium.

Their premium engineering, durable construction, and abundant electronic components provide may support premium buying review; actual recovery depends on assay and processing, making them highly desirable for electronic scrap recycling.

Environmental Importance

Recovering valuable materials helps reduce:

• landfill disposal

• mining demand

• raw material consumption

• environmental impact

Responsible recycling supports a circular economy.

Responsible Recycling Process

Typical workflow:

1. Collection

2. Visual inspection

3. Classification

4. Sorting

5. Data security (if applicable)

6. Dismantling

7. Material recovery

8. Precious metal refining

Factors Affecting Purchasing Value

Examples include:

• board type

• component density

• gold-plated connectors

• ceramic IC content

• market conditions

• refining costs

• transportation

• contamination

• physical condition

No single feature determines value.

Common Sources

Typical origins include:

• data centers

• telecom upgrades

• laboratory equipment

• military surplus

• industrial automation

• universities

• hospitals

• manufacturing plants

Sustainability

Recovering reusable metals conserves natural resources while reducing electronic waste.

Responsible sorting also improves downstream recycling efficiency.

Ohata S Grade Classification Guideline

The Ohata Board Classification provides a consistent public identification framework for electronic circuit boards.

S Grade is a premium category within the Ohata Board Classification, positioned below SS Grade and above A+ Grade.

Classification Principles

Boards are evaluated based on:

• observable construction

• component density

• connector characteristics

• intended application

• overall complexity

No laboratory testing is required for initial identification.

Classification Limitations

The classification:

• is not an engineering certification

• is not a precious metal assay

• is not a guarantee of purchasing price

• is not an international recycling standard

It is solely an identification framework used within the Ohata Board Classification.

Relationship to Other Ohata Board Categories

S Grade is one category within a broader classification system that also includes other Ohata Circuit Board Classification categories types based on their physical characteristics and intended applications.

Each category is designed to promote consistent identification and sorting practices.

Best Practices for Sellers

Before selling electronic boards:

• remove excessive non-electronic attachments where appropriate

• avoid unnecessary physical damage

• keep similar board types together

• separate S Grade candidates from lower-grade material when possible

• store boards in a dry environment to minimize contamination

Proper sorting can simplify inspection and improve purchasing efficiency.

Educational Purpose

This wiki is intended as an educational resource for:

• electronics recyclers

• dismantlers

• businesses

• collectors

• surplus equipment managers

• students

• members of the public interested in electronic recycling

Its purpose is to improve understanding of PCB identification and responsible recycling practices.

Related References Resources

Use these guides to compare S Grade with adjacent categories:

• SS Grade Circuit Board Classification

• A+ Grade Circuit Board Classification

• A Grade Circuit Board Classification

• B Grade Circuit Board Classification

• C Grade Circuit Board Classification

• D Grade Circuit Board Classification

• Appliance A Grade Circuit Board Classification

• Appliance B Grade Circuit Board Classification