Index_H

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H

Half-duplex transmission, 193

Halon fire extinguisher, 46

Hard drives

activity LED, 179

connectors, 169–170

described, 164

Disk Defragmenter, 169

EIDE interface, 173

ESDI interface, 170

extended partitions, 167

FORMAT command, 168–169, 291–292

high-level format, 168

IDE/ATA interface, 170–173

installation, configuration and troubleshooting, 178–179

IRQs, 107–108

landing zone, 164

low-level format, 168

MBR, 165, 292

partitions, 166–167, 291–292

platters, 164

POST error, 50

primary partitions, 166–167

RAID, 179–180

read/write heads, 165

S-ATA interface, 173–175

ScanDisk,169, 292–293

ST506 interface, 179

tracks, sectors, and cylinders, 165

Hardware profiles

for laptops, 123–124

Windows 2000, 392

Windows ME, 425–426

Hardware, A+ Core Hardware exam objectives, 5–19

Hazardous materials and MSDS, 46–47. See also Safety

Heat dissipation

air cooling and ATX motherboards, 41

cooling fans and heat sinks, 73

cooling fans and preventive maintenance, 45

heat sinks, 73

liquid cooling, 73–74

Hexadecimal number system, 105–106

Hidden files, 287

HIMEM.SYS, 95, 295

HMA (High Memory Area), 94, 95, 294, 505

Home Edition, Windows XP, 449–450

Hot-swapping USB devices, 199

HTML (Hypertext Markup Language), 238, 505

HTTP (Hypertext Transfer Protocol), 238, 396, 505

HTTPS (Hypertext Transfer Protocol Secure), 396

Hubs, network, 236

HVD (High-Voltage Differential) SCSI interface, 177, 505

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