CSC/ECE 506 Fall 2007/wiki1 4 JHSL

Architectual Trends

General trends

During the last ten years general direction of the architectural trends did not change much: the logic density is still increasing, number of CPUs per machine is rising, memory size and bandwidth are growing. The only difference is that the most of the yesterday's bleeding-edge technologies have made its way to consumer market and now available for individual users, not just big companies and research centers. Ready availability of such technologies, in turn, has fed the hi-end portion of the market and most of the commodity parts are preferred choice for the state-of-the art computer building. While general direction is still the same, it is important to note some of the technological advances that can potentially set new direction for the next generation of the computers.

"Rock bottom" (Silicone/Carbon)

Trend of a transistor size, current production specs and future plans.

The very basic building block of electronic technology, the transistor, has shrank dramatically during the past decade. Processors built on 45nm technology are widly available on the market. According to Intel's press release from the beginning of this year, "Just a decade ago, the state-of-the-art process technology was 250nm, meaning transistor dimensions were approximately 5.5 times the size and 30 times the area of the technology announced today by Intel" <ref>http://www.intel.com/pressroom/archive/releases/20070128comp.htm</ref>. Here, on the image below you can see a 45nm 6-transistor SRAM cell, developed by Intel.
http://www.intel.com/pressroom/images/manufacturing/45nm_SRAM_Cell_sm.jpg

Wafer size and CPU footprint

While the transistor size continues to decrease, the manufacturers have been consistently moving towards larger silicone wafer sizes. Today most of the CPUs are produces on 300mm wafers. Combined with increased logic density, this allows to produce more processors from a single wafer, therefore significantly decreasing overall production costs.
http://www.intel.com/pressroom/images/manufacturing/45nm_wafer_photo_2_sm.JPG

Longer, Wider, Deeper and Smarter:

Wider internal buses, more logical units

• (AMD K8, Intel Core 2, SSE1/2/3/4)

Deeper caches

• (L3 caches, smart prefetch and so on)

"Smarter" CPUs

• Itanium
  • (explicit parallelism)
• AMD Opteron
  • (built-in memory controller and bus logic)
• Intel P4
  • (complex branch prediction)

"My dual quad-core with quad-SLI"

Sun Niagara

• 4 threads per core
• 4 cores per CPU,
• multiple CPUs per box

"Personal Petaflop": The Latest in GPU world

• ATI Radeon
• NVidia GeForce

Buses and memory

Parallel Buses

• Past:
  • PCI
  • PCI-X
  • AGP

Serial Buses

• Future:
  • PCI-E
  • AMD HyperTransport
  • Intel EV?

Memory

• [G]DDR2/3/4
• FB-DIMM

References / Extra info

1. http://www.intel.com/pressroom/archive/releases/20070128comp.htm