C952 Computer Architecture

Explanation:

The IBM architecture, particularly the IBM POWER and later System/360 and System/370 designs, introduced innovations that allowed for the improved parallel execution of instructions. This was achieved through techniques like instruction-level parallelism, dynamic scheduling, and out-of-order execution. These concepts directly influenced modern microprocessor design, where executing multiple instructions simultaneously and optimizing instruction pipelines are essential for performance improvements. The idea of enhancing parallel execution fundamentally shaped the development of 21st-century CPUs, enabling higher throughput and more efficient use of processor resources.

Correct Answer:

Innovations allowed the improved parallel execution of instructions

Why Other Options Are Wrong:

 Prediction allowed the processor to proceed with the next instruction is incorrect because while branch prediction improved instruction flow efficiency, it was not the defining feature of IBM architecture that broadly influenced 21st-century microprocessors. It is a supporting feature rather than the primary driver of architectural influence.

Innovations allowed for dynamically scheduled pipelined processors is incorrect because dynamic scheduling and pipelining were important advancements, but they were components that facilitated parallel execution rather than the overarching feature that influenced most modern processors.

Innovations allowed for reservation stations and the commit unit is incorrect because these were specific mechanisms within out-of-order execution, which are part of parallel execution enhancements. They are not standalone architectural influences that define 21st-century microprocessor design.

Explanation:

Code efficiency in a pipelined processor is often determined by how effectively instructions flow through the pipeline without stalls or hazards. When the frequency of pipeline hazards is lower, there are fewer situations where instruction execution must be delayed due to data, control, or structural conflicts. This allows the CPU to achieve higher throughput, minimize idle cycles, and utilize resources effectively, making the code execution more efficient than conventional code that might not optimize for hazard reduction.

Correct Answer:

Frequency of pipeline hazards is lower

Why Other Options Are Wrong:

Usage of LEGv8 architecture code is incorrect because while LEGv8 is a modern RISC architecture, merely using LEGv8 instructions does not inherently make code more efficient unless pipeline hazards and instruction scheduling are properly optimized.

Usage of Multimedia extensions (MMX) is incorrect because MMX improves performance for certain multimedia operations, but it does not universally make code more efficient for all instruction types, especially in non-multimedia contexts.

Frequency of pipeline hazards is higher is incorrect because higher pipeline hazards create more stalls, delays, and inefficiencies in instruction execution, which reduces performance rather than increasing code efficiency.

Explanation:

DDR3 memory features 240 pins and provides several improvements over DDR2, including higher data transfer rates, lower power consumption, and improved latency. DDR3 achieves these improvements by operating at lower voltages and using enhanced signaling techniques. This makes DDR3 both faster and more energy-efficient compared to DDR2, which helps improve overall system performance while reducing power usage in desktop and server environments.

Correct Answer:

It features 240 pins and provides improved latency and power efficiency compared to DDR2.

Why Other Options Are Wrong:

It has 288 pins and offers higher data rates than DDR2 is incorrect because 288 pins are associated with DDR4 memory, not DDR3.

It operates at a single data rate per clock cycle, similar to DDR2 is incorrect because DDR3 is a double data rate memory that transfers data on both the rising and falling edges of the clock cycle, like DDR2, but with higher performance and efficiency.

It is primarily used in mobile devices and was introduced in the early 2000s is incorrect because DDR3 is used broadly in desktops, servers, and some laptops; it was introduced later, around 2007, not in the early 2000s.

Explanation:

In ARM assembly, the ADD instruction adds the values of two source registers and stores the result in a destination register. The instruction ADD X3, X2, X1 specifies that the values in X2 and X1 are added together, and the sum is stored in X3. This directly corresponds to the operation X3 = X2 + X1. Correct operand ordering is crucial in ARM assembly, and this instruction correctly follows the format ADD destination, source1, source2.

Correct Answer:

ADD X3, X2, X1

Why Other Options Are Wrong:

ADD X1, X2 is incorrect because it provides only two operands. ARM requires three operands for a standard addition (destination and two sources), so this instruction is incomplete and cannot perform the intended addition.

ADD X1, X2, X3 is incorrect because the destination register is incorrectly specified as X1 instead of X3. This would store the result in the wrong register.

ADD X3 X1 is incorrect because it is missing a comma and a third operand. This is not a valid ARM instruction and cannot perform the required addition.

Explanation:

DDR4 (Double Data Rate 4) memory is a modern memory technology featuring 288 pins for desktop DIMMs. It provides improved performance and efficiency compared to DDR3, including higher data transfer rates and better latency characteristics. DDR4 is widely adopted in modern desktops, laptops, and servers, offering increased bandwidth while consuming less power than DDR3, making it the standard for contemporary computing systems.

Correct Answer:

DDR4 memory features 288 pins, offers improved latency, and is widely used in modern computing devices.

Why Other Options Are Wrong:

DDR4 memory has 240 pins and operates at a lower data rate than DDR3 is incorrect because 240 pins is the count for DDR3 desktop DIMMs, and DDR4 provides higher, not lower, data rates than DDR3.

DDR4 memory is exclusively used in mobile devices and has a higher power consumption than DDR3 is incorrect because DDR4 is used in both desktops and laptops and is designed to be more power-efficient than DDR3.

DDR4 memory has 512 pins and operates at a single data rate per clock cycle is incorrect because 512 pins is not a standard for DDR4, and DDR4 operates with double data rate technology, transferring data on both rising and falling edges of the clock signal.

Explanation:

The CMOS battery provides power to the CMOS chip on the motherboard, which stores the system clock and BIOS settings even when the computer is powered off. This ensures that essential configuration information, such as boot order, date, and time, is preserved between system reboots or complete power loss. Without a functioning CMOS battery, these settings would reset to defaults each time the system is powered off.

Correct Answer:

To maintain the system clock and BIOS settings when the computer is off

Why Other Options Are Wrong:

To provide power to the CPU during operation is incorrect because the CPU receives power directly from the PSU during operation, not from the CMOS battery.

To store temporary data for running applications is incorrect because application data is stored in RAM, not the CMOS.

To power the hard drive during data retrieval is incorrect because hard drives are powered by the main system power supply, not the CMOS battery.

Explanation:

The Arithmetic Logic Unit (ALU) performs arithmetic and logic operations, but it requires data to operate on and a place to store results. The register file provides this storage for operands and results, making it essential for ALU operations. Together, the ALU and register file form the core computational elements within a processor, enabling efficient execution of instructions. Without the register file, the ALU would have no immediate access to operands or a place to store results, rendering it unable to function effectively.

Correct Answer:

ALU and register file

Why Other Options Are Wrong:

ALU and GPU is incorrect because a GPU is a specialized processor for graphics operations and is not required for general ALU operations in a CPU. The ALU operates independently of a GPU for standard arithmetic and logic tasks.

Datapath and COD is incorrect because COD is not a standard computer architecture component, and while the datapath is involved in executing operations, it cannot perform ALU functions without the ALU itself and the register file.

GPU and register file is incorrect because a GPU is not necessary for the ALU to perform basic processor operations. The ALU and register file are the essential components for implementing arithmetic and logic functions within the CPU.

Explanation:

Multitasking refers to an operating system’s ability to execute multiple applications or processes seemingly simultaneously. The OS manages CPU time by rapidly switching between tasks, giving the appearance of parallel execution even on a single-core processor. This allows users to run multiple programs at once, improving efficiency and responsiveness. True simultaneous execution can also occur on multicore or multiprocessor systems, but the term describing the OS capability itself is multitasking.

Correct Answer:

Multitasking

Why Other Options Are Wrong:

Multiprocessor is incorrect because this term describes hardware with multiple processing units, not the OS capability to manage multiple tasks.

Multicore is incorrect because it refers to a CPU with multiple cores; while it can facilitate multitasking, it does not define the OS feature itself.

Double-time is incorrect because this is not a recognized term in OS design or multitasking.

Interrupt processing is incorrect because it refers to how the OS handles external or internal events, not the general ability to run multiple processes simultaneously.

Explanation:

Recent CPU clock rates have increased while power consumption has flattened primarily due to cooling limitations. As clock speeds rise, the amount of heat generated by the processor increases. Physical limits in cooling technologies and thermal management prevent CPUs from continuing to increase power consumption proportionally with clock speed. Manufacturers have therefore optimized CPU designs for energy efficiency, using techniques such as dynamic voltage and frequency scaling (DVFS) and multi-core architectures, allowing higher performance without significantly increasing overall power usage.

Correct Answer:

Cooling issues

Why Other Options Are Wrong:

Chip sizes are too small is incorrect because smaller chip sizes allow for higher transistor density, which can improve performance and reduce power, but this is not the main reason why power consumption has flattened.

Memory size requirements is incorrect because memory size affects storage capacity and data handling but does not directly explain why CPU clock rates can increase without proportionally higher power consumption.

Chip sizes are too large is incorrect because larger chips would typically consume more power and generate more heat, which is contrary to the trend of flattened power consumption.