1.Hardware Components
1.1 Motherboard Components & Chipsets
- Chipset: Manages data flow between CPU, RAM, and peripherals
- Northbridge: Handles high-speed communication (CPU, RAM, GPU)
- Southbridge: Manages I/O devices, USB, SATA, PCIe
1.1.1 CPU (Central Processing Unit)
| Feature | Description |
| Clock Speed | Measured in GHz (higher = faster) |
| Cores | More cores = better multitasking |
| Cache | L1, L2, L3 storage for quick access |
| Hyperthreading | Virtual core splitting for efficiency |
| Cooling | Heatsinks, liquid cooling |
- Sockets:
- Intel: LGA (Land Grid Array)
- AMD: PGA (Pin Grid Array)
1.1.2 RAM (Random Access Memory)
| Type | Speed |
| DDR3 | 800 – 2133 MHz |
| DDR4 | 2133 – 4266 MHz |
| DDR5 | 4800 – 8400 MHz |
- DIMM: Desktop RAM
- SODIMM: Laptop RAM
- ECC (Error Correction Code): Used in servers for error checking
1.1.3 Storage Devices
| Type | Speed | Use Case |
| HDD (Hard Disk Drive) | Slower | Large storage (1TB+) |
| SSD (Solid-State Drive) | Faster | OS and apps |
| NVMe SSD | Fastest | High-speed data transfer |
| RAID (Redundant Array of Independent Disks) |
RAID Levels
| Level | Description |
| RAID 0 | Striping (fast, no redundancy) |
| RAID 1 | Mirroring (redundant, slower) |
| RAID 5 | Striping + parity (3+ disks, redundancy) |
| RAID 10 | Striping + mirroring (4+ disks) |
1.2.Input/Output & Peripherals
1.2.1 Ports & Connectors
| Connector | Purpose |
| USB 2.0 | 480 Mbps |
| USB 3.0 | 5 Gbps |
| USB 3.1 | 10 Gbps |
| USB-C | 40 Gbps (Thunderbolt 3) |
| HDMI | Audio & video |
| DisplayPort | High-resolution video |
| Ethernet (RJ-45) | Networking |
1.3.Power & Cooling
- PSU (Power Supply Unit):
- Wattage: 400W – 1000W+
- 80 PLUS Certification: Efficiency rating
- Cooling Solutions:
- Air Cooling: Fans, heatsinks
- Liquid Cooling: Water blocks, radiators
1.4.Printers & Troubleshooting
| Printer Type | Feature |
| Laser | Toner-based, fast, expensive |
| Inkjet | Liquid ink, color printing |
| Thermal | Heat-sensitive paper (receipts) |
| Impact (Dot Matrix) | Used in legacy systems |
Common Issues & Fixes
- Paper jams → Check rollers
- Faded prints → Replace toner
- Streaks → Clean print heads
5.Networking Basics (For A+)
- IP Addressing:
- IPv4: 192.168.1.1
- IPv6: FE80::1
- Subnet Mask: Defines network portion of an IP
- Default Gateway: Router IP address
- DNS: Resolves domain names to IPs
2.CompTIA Network+ Cheat Sheet
2.1Networking Concepts
2.1.1 OSI Model (7 Layers)
| Layer | Function |
| 7. Application | HTTP, FTP, SMTP |
| 6. Presentation | Encryption, compression |
| 5. Session | Manages connections |
| 4. Transport | TCP, UDP (reliable/unreliable transport) |
| 3. Network | IP, routing, subnetting |
| 2. Data Link | MAC addresses, switches |
| 1. Physical | Cables, hubs |
2.1.2 TCP/IP Model (4 Layers)
| TCP/IP Layer | OSI Equivalent |
| Application | App, Presentation, Session |
| Transport | Transport |
| Internet | Network |
| Network Access | Data Link, Physical |
2.2.IP Addressing & Subnetting
| Address Type | Example | Purpose |
| Private IPv4 | 192.168.1.1 | LAN use |
| Public IPv4 | 8.8.8.8 | Internet use |
| IPv6 | FE80::1 | New standard |
- Subnetting Example
- Subnet Mask: 255.255.255.0 (/24)
- CIDR Notation: 192.168.1.0/24
- Hosts per subnet: 254
- Calculate Subnets
ipcalc 192.168.1.0/24
2.3.Network Devices & Protocols
| Device | Function |
| Router | Connects networks |
| Switch | Connects devices (Layer 2) |
| Firewall | Controls network security |
| Access Point | Extends Wi-Fi |
| Modem | Converts digital to analog |
Common Network Protocols
| Protocol | Function |
| HTTP/HTTPS | Web browsing |
| FTP | File transfers |
| DNS | Domain resolution |
| DHCP | Assigns IPs |
| SSH | Secure remote login |
| SNMP | Network monitoring |
2.4.Wireless & Security
| Standard | Speed | Frequency |
| 802.11a | 54 Mbps | 5 GHz |
| 802.11b | 11 Mbps | 2.4 GHz |
| 802.11g | 54 Mbps | 2.4 GHz |
| 802.11n | 600 Mbps | 2.4/5 GHz |
| 802.11ac | 1 Gbps | 5 GHz |
| 802.11ax (Wi-Fi 6) | 9.6 Gbps | 2.4/5 GHz |
Encryption Types
| Type | Security Level |
| WEP | Weak |
| WPA | Medium |
| WPA2 | Strong |
| WPA3 | Strongest |
2.5.Network Troubleshooting
Command Line Tools
| Command | Purpose |
| ping | Test connectivity |
| tracert | Trace route to a destination |
| ipconfig /all | Show IP settings |
| nslookup | Query DNS records |
| netstat | View network connections |
