Computing Fundamentals Flashcards

A technician installs a new 4 TB drive as the only drive in an older PC and installs the OS in legacy BIOS mode. Disk Management shows only about 2 TB as usable, and the rest is listed as unallocated space that can't be added to the partition. What is the most likely cause?

Answer: The disk was set up with an MBR partition table, which cannot address more than about 2 TB

MBR (Master Boot Record) stores partition sizes and locations as 32-bit sector values. With 512-byte sectors, that limits it to about 2 TB. Legacy BIOS booting needs MBR, so the extra space can't be used. Converting the disk to GPT and booting in UEFI mode removes the limit. NTFS supports volumes far larger than 2 TB, and IDE mode doesn't cap capacity this way.

A workstation has 16 GB of RAM installed, but the system information screen reports only about 3.2 GB as usable. All memory modules pass diagnostics. What best explains this?

Answer: A 32-bit operating system is installed, so it can address only about 4 GB, and some of that range is reserved for hardware

A 32-bit OS can address at most 2^32 bytes, which is 4 GB. Part of that address range is reserved for devices such as the video card and the PCIe bus, so usable memory often shows as about 3–3.5 GB. Installing a 64-bit OS lets the system use all 16 GB. Single-channel mode lowers bandwidth, not capacity. Shared video memory never takes 80% of RAM.

A user buys a drive labeled "1 TB." After formatting it, the operating system reports about 931 GB of total capacity. What is the main reason for the difference?

Answer: Manufacturers measure in decimal units (1 TB = 10^12 bytes), while the OS reports in binary units (1 GiB = 2^30 bytes)

Drive makers define 1 TB as 1,000,000,000,000 bytes. Windows divides by 1024³ (1,073,741,824) but still labels the result "GB." 10^12 ÷ 1,073,741,824 ≈ 931. The drive isn't missing any space. The two sides are just using different units. File system overhead is real, but it is tiny compared with this gap.

A user is leaving for a 4-day trip. Their laptop battery will fully drain while they are away, and they can't plug it in. They want to come back and find every open application and unsaved document exactly as they left it. Which power option should they choose?

Answer: Hibernate, because it writes the contents of RAM to the storage drive and then cuts power completely

Hibernate saves the full memory state to a file on the drive (hiberfil.sys on Windows) and then turns the computer off completely. The session survives even if the battery runs to zero. Sleep keeps RAM powered, so if the battery dies, everything unsaved is lost. Fast Startup only saves the kernel session, not the user's open applications. Locking the screen doesn't save anything.

A technician sets up a monthly maintenance plan for a laptop that has only a solid-state drive (SSD). Which task should NOT be included, because it gives no performance benefit and adds unnecessary wear?

Answer: Running a traditional defragmentation pass that physically rearranges file blocks

Defragmentation helps hard drives by reducing how far the read head has to move. An SSD has no moving parts and reads any block in the same time, so rearranging files gives no speed benefit. It just uses up write cycles, which are limited on flash memory. Modern operating systems detect SSDs and send TRIM instead of defragmenting. Firmware updates, TRIM, and S.M.A.R.T. checks are all good SSD maintenance.

A computer's CPU specification lists 4 physical cores, but Task Manager shows 8 processors in its CPU graphs. What is the most accurate explanation?

Answer: The CPU supports simultaneous multithreading (such as Hyper-Threading), so each physical core appears as two logical processors

Simultaneous multithreading lets one physical core run two instruction threads at the same time by sharing its execution resources. The OS treats each thread as its own logical processor, so 4 cores × 2 threads = 8 logical processors. This often improves throughput, but it doesn't double performance, because the two threads share the same core hardware.