- A+ Certification
- A+ 220-1001: Day 1: Intro, Resources & the Test
- A+ 220-1001: Day 2: CPUs
- A+ 220-1001: Day 2: RAM
- A+ 220-1001: Day 3: Firmware, Motherboards & Power Supplies
- A+ 220-1001: Day 4: Disks & Mass Storage
- A+ 220-1001: Day 5: Peripherals & PC Builds
- A+ 220-1001: Day 6: Windows Operations, User Management & Windows Maintenance
- A+ 220-1001: Day 7: The Command Line & Troubleshooting
- A+ 220-1001: Day 8: Displays & Networking
- A+ 220-1002: Day 9: Ethernet & WiFi
- A+ 220-1002: Day 10: The Internet & Virtualization
- A+ 220-1002: Day 11: Portable & Mobile Computing
- A+ 220-1002: Day 12: Mobile Administration & Printing
- A+ 220-1002: Day 13: Security & Operations
- A+ 220-1002: Day 14:
- A+ 220-1002: Day 15:
BIOS and CMOS
Old IO: serial, parallel, PCI, old USB, IDE, SATA, ethernet, audio, CMOS
New, fast IO: PCIe (PCI Express), HyperTransport, Infinity Fabric
How Memory Controllers Used to Work
How Memory Controller Buses Work Now
PCI was the “new” bus that replaced the ISA bus.
It functions like a network switch: every device gets full bus speed, a totally separate communication bus, and “plug and play” auto-configuration.
PCI slots run at 33mhz, 32bits bandwidth, for a total bandwidth (per device) of 133MBps.
There ARE 66mhz PCI buses, though these are rare.
And there ARE 5v and 3.3v PCI slots (which accounts for the different frequencies).
There are also 64bit PCI buses, which use a longer slot: PCI-X.
PCI-X (PCI Expanded)
PCIe (PCI Express)
Lanes: x1, x2, x4, x8, x16
v1, v2, v3, v4
–> Note that some PCIe lanes may be built into the CPU. Some of these may be used for core interconnects. Other PCIe lanes may be provided externally from the frontside bus (IO) controller.
IDE/ATA and SATA
Old ribbon-cable IDE (ATA) drives ran at 33MBps, and used a 40-wire cable.
Later generations ran at 66, 100 and 133 MBps, and required an 80-wire cable (to prevent cross-talk).
First-gen SATA ran at 150MBps, so it wasn’t much of an increase, though management was much easier. You can have SATA RAID, but not IDE RAID.
SATA-2 runs at 300MBps, and SATA-3 runs at 600MBps.
M.2 Slot Drives
M.2 slots can be used for SSDs, wifi or wireless cards, or any accessory that needs big bandwidth.
M.2 slots can be EITHER:
–> A SATA SSD in an M.2 slot will max out at SATA speeds, i.e. 600MBps maximum.
M.2 slots connect on the back end to either 2 or 4 PCIe lanes (obviously 4 is better).
–> An NVME SSD in an M.2 slot will be hugely faster than SATA, i.e. up to 3500MBps!
Switching, motherboard interfaces, plugs and maintenance
12v, 5v, 3.3v, 12v ground, 5v ground
Dual-legged or multi-legged
Modular power supplies
20/24-pin motherboard power plug
PCIe power plugs (6 and 8 wire)
Chapters 5, 6 and 7