A+ Core 1 3.5 — ATX vs micro-ATX vs Mini-ITX: size, slots, power (20/24-pin) and shared ATX mounting.
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#comptia
104 entries across collections.
A+ Core 1 3.5 — buses, PCI (parallel, 32/64-bit) vs PCIe (serial, lanes), keying, and safe card installation.
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A+ Core 1 3.5 — main and PCIe power connectors, SATA/eSATA, front-panel/USB/TPM headers, and M.2.
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A+ Core 1 3.5 — Intel vs AMD sockets, zero-force CPU install, and multisocket server motherboards.
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A+ Core 1 3.5 — BIOS firmware, POST and boot, legacy BIOS vs UEFI, dual-BIOS flash, and safe setting changes.
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A+ Core 1 3.5 — entering setup, boot order, USB control, fans/temps, Secure Boot, boot vs supervisor passwords, CMOS reset, virtualisation.
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A+ Core 1 3.5 — TPM (on-board crypto, root of trust, BitLocker) vs HSM (centralised keys and crypto offload).
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A+ Core 1 3.5 — 32-bit vs 64-bit (x86/x64), ARM architecture, and multi-core CPUs.
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A+ Core 1 3.5 — sound cards, integrated vs discrete GPUs, capture cards, NICs, and driver install best practice.
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A+ Core 1 3.5 — fans and airflow, passive cooling, heat sinks, thermal paste vs pads, and liquid cooling.
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A+ Core 1 3.7 — MFD setup, drivers, PCL/PostScript, connectivity, sharing, print features, secure printing, and scanning.
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A+ Core 1 3.8 — laser imaging process, toner/OPC drum, cartridge and maintenance-kit replacement, calibration, and safe cleaning.
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A+ Core 1 3.8 — inkjet operation, CMYK cartridges, print heads, feed rollers, duplex, plus carriage/belt and calibration.
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A+ Core 1 3.8 — cleaning inkjet print heads, replacing CMYK cartridges, calibration, and clearing paper jams.
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A+ Core 1 3.8 — how thermal printers work, the feed assembly and heating element, thermal paper, and handling output safely.
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A+ Core 1 3.8 — replacing thermal paper, cleaning the heating element with IPA, removing debris safely, and heat/fade sensitivity.
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A+ Core 1 3.8 — dot-matrix print heads, ribbons, tractor-feed paper, green bar paper, and multi-part carbonless copies.
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A+ Core 1 3.8 — ribbon replacement, print head replacement, and continuous tractor-feed paper handling on dot-matrix printers.
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Full class notes for A+ Core 1 3.5: choosing between ATX, micro-ATX and Mini-ITX by size, slots, power and mounting.
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Full class notes for A+ Core 1 3.5: buses, PCI vs PCIe, parallel vs serial, PCIe lanes, and installing add-in cards safely.
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Full class notes for A+ Core 1 3.5: main and PCIe power connectors, SATA/eSATA data, front-panel and USB/TPM headers, and M.2.
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Full class notes for A+ Core 1 3.5: Intel vs AMD sockets, installing a CPU, and multisocket server motherboards.
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Full class notes for A+ Core 1 3.5: BIOS firmware, POST and boot, legacy BIOS vs UEFI, dual-BIOS flash, and settings.
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Full class notes for A+ Core 1 3.5: entering setup, boot order, USB control, fan and temperature, Secure Boot, passwords, CMOS reset and virtualisation.
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Full class notes for A+ Core 1 3.5: protecting cryptographic keys with a TPM (root of trust, BitLocker) and centralising them with an HSM.
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Full class notes for A+ Core 1 3.5: 32-bit vs 64-bit (x86/x64), ARM architecture, and multi-core CPUs.
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Full class notes for A+ Core 1 3.5: sound cards, discrete GPUs, capture cards, NICs, and driver install best practice.
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Full class notes for A+ Core 1 3.5: fans and airflow, passive cooling, heat sinks, thermal paste and pads, and liquid cooling.
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Full class notes for A+ Core 1 3.7: MFD setup, drivers, PCL/PostScript, connectivity, sharing, print features, secure printing, and scanning.
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Full class notes for A+ Core 1 3.8: the laser imaging process, toner/OPC drum, cartridge and maintenance-kit replacement, calibration, and cleaning.
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Full class notes for A+ Core 1 3.8: inkjet operation, CMYK cartridges, print heads, feed rollers, duplex, and (beyond the clip) carriage/belt and calibration.
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Full class notes for A+ Core 1 3.8: cleaning inkjet print heads, replacing CMYK cartridges, calibration, and clearing paper jams.
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Full class notes for A+ Core 1 3.8: how thermal printers work, the feed assembly and heating element, thermal paper care, and handling output.
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Full class notes for A+ Core 1 3.8: replacing thermal paper, cleaning the heating element, removing debris safely, and heat/fade sensitivity.
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Full class notes for A+ Core 1 3.8: dot-matrix print heads, ribbons, tractor-feed paper, and multi-part carbonless copies.
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Full class notes for A+ Core 1 3.8: ribbon replacement, print head replacement, and continuous tractor-feed paper handling on dot-matrix printers.
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Professor Messer A+ 220-1201 objective 3.1 — LCD backlights, TN vs IPS vs VA, OLED, mini LED local dimming, digitizers and styluses, inverters and the torch test.
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Professor Messer A+ 220-1201 objective 3.1 — pixel density and PPI maths, refresh rate vs FPS and V-sync, resolution and aspect ratio, and colour gamut percentages.
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Professor Messer A+ 220-1201 objective 3.2 — twisted pair and why it is twisted, categories and distances, coax, UTP vs STP shielding codes, direct burial and plenum-rated cable.
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Professor Messer A+ 220-1201 objective 3.2 — ANSI/TIA-568 and ISO/IEC 11801, the T568A and T568B pinouts, the four pins that differ, crimping checks and keystone jacks.
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Professor Messer A+ 220-1201 objective 3.2 — light through core and cladding, ferrules and connectors, and multimode vs single-mode fibre on distance, source and core size.
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Professor Messer A+ 220-1201 objective 3.2 — USB versions and speeds, connector types and USB-C, DB-9 serial, RS-232 console access, and Thunderbolt 1 to 4.
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Professor Messer A+ 220-1201 objective 3.2 — HDMI, DisplayPort and its locking connector, DVI variants and single/dual link, VGA, and video over USB-C.
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Professor Messer A+ 220-1201 objective 3.2 — SATA revisions and speeds, the one-to-one power and data connectors, no daisy chaining, and eSATA.
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Professor Messer A+ 220-1201 objective 3.2 — DVI-D to HDMI and DVI-A to VGA compatibility, USB-to-Ethernet and USB-C-to-USB-A adapters, and USB hubs.
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Professor Messer A+ 220-1201 objective 3.2 — RJ11 and RJ45, F connectors and DOCSIS, punchdown blocks, USB and USB-C, Molex, Lightning, and DB-9/RS-232.
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Professor Messer A+ 220-1201 objective 3.2 — ST bayonet, SC push-pull, and LC clip connectors for optical fibre, compared by mechanism and size.
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Professor Messer A+ 220-1201 objective 3.3 — RAM vs storage, DIMM and SO-DIMM, 64-bit data width, SDRAM, double data rate, and DDR3/DDR4/DDR5 compatibility and keying.
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Professor Messer A+ 220-1201 objective 3.3 — parity memory and even-parity calculation, ECC memory, memory bandwidth in MT/s, and multi-channel RAM.
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Professor Messer A+ 220-1201 objective 3.4 — hard drives and RPM, SSDs, PCIe and NVMe, SAS, mSATA and M.2 keying, flash memory formats, and optical drives.
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Professor Messer A+ 220-1201 objective 3.4 — RAID 0 striping, RAID 1 mirroring, RAID 5 and RAID 6 parity, and nested RAID 1+0, plus why RAID is not backup.
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Professor Messer A+ 220-1201 objective 3.6 — power supply safety, AC vs DC, amps/volts/watts, regional voltage, the 24-pin connector, redundant PSUs, modular cabling, sizing, and 80 PLUS efficiency.
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Full class notes for Professor Messer A+ 220-1201 objective 3.1: LCD backlights, TN vs IPS vs VA, OLED, mini LED local dimming, touchscreens and digitizers, and inverters.
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Full class notes for Professor Messer A+ 220-1201 objective 3.1: pixel density and PPI maths, refresh rate and frames per second, resolution and aspect ratio, and colour gamut.
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Full class notes for Professor Messer A+ 220-1201 objective 3.2: twisted pair and why it is twisted, cable categories and distances, coax, UTP vs STP shielding codes, direct burial and plenum-rated cable.
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Full class notes for Professor Messer A+ 220-1201 objective 3.2: ANSI/TIA-568 and ISO/IEC 11801, the T568A and T568B pinouts, what differs between them, and wiring keystone jacks.
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Full class notes for Professor Messer A+ 220-1201 objective 3.2: how light travels through a fibre core and cladding, ferrules and connectors, and multimode versus single-mode fibre.
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Full class notes for Professor Messer A+ 220-1201 objective 3.2: USB versions and speeds, USB connector types and USB-C, DB-9 serial and RS-232 console access, and Thunderbolt 1 to 4.
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Full class notes for Professor Messer A+ 220-1201 objective 3.2: SATA revisions and speeds, the one-to-one SATA power and data connectors, and eSATA.
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Full class notes for Professor Messer A+ 220-1201 objective 3.2: DVI-D to HDMI and DVI-A to VGA compatibility, USB-to-Ethernet and USB-C-to-USB-A adapters, and USB hubs.
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Full class notes for Professor Messer A+ 220-1201 objective 3.2: RJ11 and RJ45, F connectors and DOCSIS, punchdown blocks, USB and USB-C, Molex, Lightning, and DB-9/RS-232.
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Full class notes for Professor Messer A+ 220-1201 objective 3.2: ST bayonet connectors, SC push-pull connectors, and compact LC connectors for optical fibre.
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Full class notes for Professor Messer A+ 220-1201 objective 3.3: RAM vs storage, DIMM and SO-DIMM, 64-bit data width, SDRAM, double data rate, and DDR3/DDR4/DDR5 compatibility and keying.
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Full class notes for Professor Messer A+ 220-1201 objective 3.3: parity memory and even-parity calculation, ECC memory, memory bandwidth in MT/s, and multi-channel RAM.
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Full class notes for Professor Messer A+ 220-1201 objective 3.4: hard drives and RPM, SSDs, PCIe and NVMe, SAS, mSATA and M.2 keying, flash memory formats, and optical drives.
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Full class notes for Professor Messer A+ 220-1201 objective 3.4: RAID 0 striping, RAID 1 mirroring, RAID 5 and RAID 6 parity, and nested RAID 1+0.
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Full class notes for Professor Messer A+ 220-1201 objective 3.6: power supply safety, AC vs DC, amps/volts/watts, regional voltage, the 24-pin connector, redundant PSUs, modular cabling, wattage sizing, and 80 PLUS efficiency.
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Full class notes for Professor Messer A+ 220-1201 objective 3.2: HDMI, DisplayPort and its locking connector, DVI variants and single/dual link, VGA, and video over USB-C.
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Professor Messer A+ 220-1201 objective 2.7 — satellite (GEO vs LEO), fibre, cable and DOCSIS, DSL, cellular tethering vs hotspot, and WISPs.
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Professor Messer A+ 220-1201 objective 2.8 — crimpers, Wi-Fi and spectrum analysers, tone generator and probe, punch-down tools, cable testers, loopback plugs, taps and SPAN.
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Full class notes for Professor Messer A+ 220-1201 objective 2.7: satellite (GEO vs LEO), fibre, cable and DOCSIS, DSL, cellular tethering and hotspots, and WISPs.
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Full class notes for Professor Messer A+ 220-1201 objective 2.8: crimpers, Wi-Fi and spectrum analysers, tone generator and probe, punch-down tools, cable testers, loopback plugs, taps and port mirrors.
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Professor Messer A+ 220-1201 section 2 — IP, TCP/UDP and ports, wireless, network services, DNS/DHCP/VLAN/VPN, devices, IP addressing, connection types and tools.
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Professor Messer A+ 220-1201 objective 2.5 — routers, managed vs unmanaged switches, access points, patch panels, firewalls, PoE standards, cable/DSL/ONT and NICs.
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Professor Messer A+ 220-1201 objective 2.6 — IPv4 octets and binary, RFC 1918 private ranges and NAT, IPv6 hex notation, shortening rules, address types and /64.
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Professor Messer A+ 220-1201 objective 2.6 — IP address, subnet mask and gateway; static vs dynamic vs DHCP reservation; APIPA range and its ARP check.
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Full class notes for Professor Messer A+ 220-1201 objective 2.5: routers, managed and unmanaged switches, access points, firewalls, PoE and ISP devices.
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Full class notes for Professor Messer A+ 220-1201 objective 2.6: IPv4 structure and binary, RFC 1918 private ranges and NAT, IPv6 notation and /64 prefixes.
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Full class notes for Professor Messer A+ 220-1201 objective 2.6: IP address, subnet mask and gateway; static addressing vs DHCP reservations; APIPA.
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Professor Messer A+ 220-1201 lesson 1.1 — laptop batteries, keyboards, SO-DIMM memory, 2.5-inch vs M.2 storage, HDD-to-SSD cloning, wireless cards and antennas, biometrics, NFC and cameras.
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Professor Messer A+ 220-1201 lesson on connecting mobile devices — mini/micro-USB, Type-A, USB-C, Lightning, NFC, Bluetooth PAN, hotspot vs tethering.
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Professor Messer A+ 220-1201 lesson on mobile accessories — stylus, headsets and TRRS, speakers, webcams, docking station vs port replicator, trackpads and drawing pads.
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Professor Messer A+ 220-1201 lesson on MDM — BYOD, COPE, CYOD, partitioning, policies and restrictions, the MDM console and IMEI, over-the-air sync and business app accounts.
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Professor Messer A+ 220-1201 networking primer — encapsulation, TCP vs UDP, multiplexing, IP addresses, well-known vs ephemeral ports, reading a protocol decode.
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Professor Messer A+ 220-1201 objective 2.1 — FTP, SSH, Telnet, SMTP, DNS, DHCP, HTTP/HTTPS, POP3, IMAP, SMB/CIFS, NetBIOS, LDAP and RDP port numbers.
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Professor Messer A+ 220-1201 objective 2.2 — 802.11/Wi-Fi naming, frequency bands, channels and bandwidth, Bluetooth and ISM, RFID passive/active tags, and NFC.
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Professor Messer A+ 220-1201 objective 2.3 — DNS, DHCP, file/print sharing, email, syslog/SIEM, web, AAA, database, NTP, spam gateway, UTM, load balancer, proxy, SCADA/ICS, legacy, embedded and IoT.
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Professor Messer A+ 220-1201 objective 2.4 — DNS hierarchy and root servers, dig/nslookup, resource records, A/AAAA, CNAME, MX, TXT, DKIM, SPF and DMARC.
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Professor Messer A+ 220-1201 objective 2.4 — why DHCP exists, the DORA process with exact packet fields, scopes, pools and exclusions, and DHCP reservations.
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Professor Messer A+ 220-1201 objective 2.4 — broadcast domains, LANs, VLANs and inter-VLAN routing, VPN concentrators, client-to-site vs site-to-site VPN.
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Exam tip: on the 220-1201 exam, display technologies (LCD, OLED, digitizers, inverters) moved to section 3 (Hardware). Section 1 is laptop hardware, connections and connectivity/management.
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A laptop packs a full computer into a very small space. That's why it's the standard platform for anyone on the move — but it's also why laptops are harder to service:
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Almost everyone in an organisation carries a phone, a tablet or both. Each device needs a way to connect back to computers and networks — and different devices have historically used different connectors and standards.
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Fingers work well for tapping and swiping, but they're imprecise. A digital stylus works like a pen or pencil on the screen, giving much finer, more granular control — for handwriting, drawing, annotating documents…
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An organisation may have hundreds or thousands of phones and tablets. Some are company-owned; others belong to employees. They're outside the office, easily lost, and each needs the right apps, email settings and…
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Data sent across a network is wrapped in layers, like envelopes inside envelopes (
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Note: this video doesn't map directly to an exam objective. Messer presents it as a primer: everything in the networking domain builds on it, so it's worth learning well.
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You'll use these port numbers in two everyday situations:
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When people say "wireless networking", they usually mean the network used at home or work to reach other devices and the internet. This is standardised by the IEEE — the Institute of Electrical and Electronics…
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A typical data centre holds rack after rack of equipment, with many different services running across those racks. This lesson works through the services you'd expect to find there — and several you'll meet…
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DNS (Domain Name System) is one of the most critical services on any network. It lets us provide IP addresses when all we remember is a fully qualified domain name (FQDN).
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Before automatic addressing, every device's IP configuration — IP address, subnet mask, default gateway, DNS servers and other settings — had to be entered manually. That was manageable with a small number of devices…
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A LAN (Local Area Network) is a group of devices connected together into a single broadcast domain. Send a broadcast from one device on that LAN, and every other device on that same LAN sees it.
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Professor Messer A+ 220-1201 section 1 — laptop hardware, connecting and accessorising mobile devices, cellular and wireless connectivity, and MDM.
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