Raghu Machiraju Slides: Courtesy - Prof. Huamin Wang, CSE, OSU CSE 581: Module 2 - Hardware Raghu Machiraju Slides: Courtesy - Prof. Huamin Wang, CSE, OSU

Architecture Keyboard and mouse Graphics card Power CPU Hard drive DVD ROM Memory

Raster Graphics Systems Raster: Images are represented by an array of picture elements (pixels).

Frame Buffer Screen resolution Refresh rate Pixel format 1 bit: black & white 8 bits: 256 levels of gray 32 bits: 16 million colors (true color)

Size of Frame Buffer Number of pixels × Bits per pixel Screen resolution Pixel format For example, the screen is 1960×1080 with 24 bits per pixel, how big is the frame buffer? Frame buffer may store other information, such as depth values. 1960×1080×24=51M bits = 6M bytes

A Prototype Graphics System CPU Memory Frame buffer in main memory? Frame buffer System bus (motherboard) Video controller

An Early Graphics System CPU Memory System bus (motherboard) Graphics memory: on-board frame buffer for faster access Graphics memory Video controller Graphics card/video card/display card

An Early Graphics System CPU Memory System bus (motherboard) A processor dedicated for graphics processing Graphics memory Video controller Graphics processor (GPU) Graphics card

Companies Building Graphics Cards

Comparison (Flops: Floating-point operations)

Evaluation

Graphics Pipeline: Software

Graphics Pipeline: Hardware Geometry stage Rasterization stage

Graphics Bus Interface: Peripheral Component Interconnect (PCI) CPU Memory System bus (motherboard) PCI bus 133MB/s Other peripherals: wireless card, sound card, … Graphics memory Video controller Graphics processor (GPU) Graphics card

Problems with PCI PCI bus becomes a bottleneck! Shared with other devices. Lots of data from main memory to graphics memory: textures, geometry… Example: 2M triangles, 90 bytes each => 180 MB > 133 MB (PCI bandwidth)

Graphics Bus Interface: Accelerated Graphics Port (AGP) CPU Memory System bus (motherboard) PCI bus AGP bus AGP 1.1: 533 MB/s AGP 3.0: 2133 MB/s 132 MB/s Other peripherals: wireless card, sound card, … Graphics memory Video controller Graphics processor (GPU) Graphics card

Features of AGP No local bus congestion. Faster data transfer (20 times faster than PCI). More geometry can be transferred. Direct execution of many operations from the man memory.

Graphics Bus Interface: Peripheral Component Interconnect Express (PCI-e) CPU Memory System bus (motherboard) 3GB/s (Shared, parallel) PCI-e bus Other peripherals: wireless card, sound card, … Graphics memory Video controller Graphics processor (GPU) Graphics card

Readings & Labs Textbook: Chapter 1 & 2