The board that ties everything together — a quick-reference cheat sheet, not a deep dive.
| Form Factor | Size | Notable Facts |
|---|---|---|
| ATX (Advanced Technology Extended) | 12" x 9.6" | Created by Intel, 1995 |
| Micro-ATX (µATX) | 9.6" x 9.6" | ~25% shorter than ATX |
| Mini-ITX (ITX = Information Technology eXtended) | 6.7" x 6.7" | Smallest common size; fanless-capable |
| Half | Handles | Notable Facts |
|---|---|---|
| Northbridge | Fast devices (RAM, video) | Now built directly into the CPU |
| Southbridge | Slower devices (USB, disk) | aka I/O Controller Hub (Intel) / Fusion Controller Hub (AMD) |
| Term | Type | Notable Facts |
|---|---|---|
| ROM (Read-Only Memory) | Nonvolatile chip | Stores startup code |
| CMOS (Complementary Metal-Oxide Semiconductor) | Battery-backed memory | Stores boot order, passwords, settings |
| BIOS (Basic Input/Output System) | Firmware | The actual startup code (≠ CMOS, which is just the settings menu) |
| UEFI (Unified Extensible Firmware Interface) | Firmware | Replaced BIOS starting 2007; standard on PCs since ~2014 |
| Standard | Notable Facts |
|---|---|
| PCI (Peripheral Component Interconnect) | Legacy parallel-bus expansion standard; mostly obsolete today |
| PCIe (PCI Express) | Current serial-bus standard — used for GPUs, NICs, sound cards, NVMe storage |
| x1 / x4 / x8 / x16 | Physical slot sizes — more lanes = more bandwidth |
| PCIe x16 | Standard slot for graphics cards — highest bandwidth |
| 6-pin / 8-pin PCIe power | Supplies extra power directly to GPUs (75W / 150W) beyond what the slot provides |
| Mini-PCIe | Compact version used in laptops for Wi-Fi/Bluetooth cards |
| Component | Notable Facts |
|---|---|
| Control unit | Directs CPU operations — the "traffic cop" |
| ALU (Arithmetic Logic Unit) | Performs math & logic operations |
| Registers | Tiny, ultra-fast onboard storage |
| Cache (L1/L2/L3) | Built from SRAM; closer tiers = faster but smaller |
| PGA (Pin Grid Array) → LGA (Land Grid Array) | Socket pin design switched in 2004 |
| Clock speed | 4.77MHz (1979, Intel 8088) → 5GHz+ today |
| Type | Notable Facts |
|---|---|
| DRAM (Dynamic RAM) | Capacitor-based; needs constant refresh |
| SRAM (Static RAM) | Flip-flop based; faster, used for CPU cache |
| DDR (Double Data Rate) → DDR5 | Each generation roughly doubles speed |
| Feature | Notable Facts |
|---|---|
| MAC (Media Access Control) address | 48-bit, burned in, globally unique |
| Wired | RJ-45 / Ethernet cable |
| Wireless | Radio link to an access point |
| OSI (Open Systems Interconnection) layers | Spans Layer 1 (physical) & Layer 2 (data link) |
| Standard | Max Speed |
|---|---|
| USB 1.0 | 12 Mbps |
| USB 2.0 | 480 Mbps |
| USB 3.1 Gen 1 | 5 Gbps |
| USB 3.1 Gen 2 | 10 Gbps |
| USB 3.2 | 20 Gbps |
| Thunderbolt 3 | 40 Gbps |
| Connector | Signal | Notable Facts |
|---|---|---|
| VGA (Video Graphics Array) / SVGA (Super Video Graphics Array) | Analog | Legacy CRT-era standard; prone to noise/distortion; still shows up on budget monitors |
| DVI (Digital Visual Interface) | Digital | Built for LCD/plasma displays; cleaner signal than VGA, no audio |
| S-Video (Separate Video) | Analog | Legacy; used for DVDs/game consoles; rare on modern PCs |
| HDMI (High-Definition Multimedia Interface) | Digital | Carries audio + video together; today's most common port |
| DisplayPort | Digital | Drives multiple monitors from one cable; up to 3840x2400 on a single display |
| Jack / Source | Signal | Notable Facts |
|---|---|---|
| Line-out (speaker) | Analog | Standard 3.5mm jack; most common audio output |
| Mic-in | Analog | Lower voltage than line-in; used for speech recognition & VoIP |
| USB audio adapter | Digital dongle | USB-A on one end, 3.5mm jacks on the other; bypasses onboard audio entirely |