1. CSIT 301 (Blum)1 Processor Specs

2. CSIT 301 (Blum)2 Pentium 4 Processor Specs

3. CSIT 301 (Blum)3 The above list of processor specifications includes such aspects as CPU Speed, Bus Speed, Manufacturing technology, Stepping, Cache Size, Package Type

4. CSIT 301 (Blum)4 Some more recent processor spec’s

5. CSIT 301 (Blum)5 CPU Speed

6. CSIT 301 (Blum)6 CPU Speed

7. CSIT 301 (Blum)7 CPU Speed The activities of the processor are kept in sync by the clock. The clock goes through a regular/repetitive action. In a binary system, a cycle consists of a 1 and a 0 (a high followed by a low). The clock is usually a quartz oscillator that is external to the microprocessor. So the CPU speed is not something built into the chip, but rather the maximum rate at which the chip can be expected to perform normally.

8. CSIT 301 (Blum)8 CPU Speed (Cont.) Sometimes differently rated chips are made from the same manufacturing process, and the CPU speed is determined by some testing after the fact. Some people try to operate the processor faster than the designated rate. This is known as “overclocking.”

9. CSIT 301 (Blum)9 CPU Speed (Cont.) The speed is measured in Hertz, which are cycles per second. –KiloHertz, kHz, is thousands (10 3 ) of cycles per second –MegaHertz, MHz, is millions (10 6 ) of cycles per second –GigaHertz, GHz, is billions (10 9 ) of cycles per second –What’s next?

10. CSIT 301 (Blum)10 CPU Speed (Cont.) The clock speed is also known as the clock’s frequency (the number of cycles per second). A related quantity is called the period which is the time required for one cycle (a.k.a. as a clock tick). A clock’s frequency and period are reciprocals. –f = 1/T or T = 1/f, where f is frequency and T is period –E.g. a frequency of 60 Hertz (cycles per second) corresponds to a period of 1/60 = 0.0167 seconds per cycle

11. CSIT 301 (Blum)11 CPU Speed (Cont.) A frequency of 1 kHz [a thousand cycles per second] corresponds to a period (tick) of 1 millisecond (ms) [a thousandth (10 -3 ) of a second per cycle]. A frequency of 1 MHz [a million cycles per second] corresponds to a period (tick) of 1 microsecond (  s) [a millionth (10 -6 ) of a second per cycle]. A frequency of 1 GHz [a billion cycles per second] corresponds to a period (tick) of 1 nanosecond (ns) [a billionth (10 -9 ) of a second per cycle].

12. CSIT 301 (Blum)12 Bus Speed

13. CSIT 301 (Blum)13 Bus Speed

14. CSIT 301 (Blum)14 Bus Speed There is a hierarchy of buses in a computer, but in a discussion of processors, the buses of interest are the front-side bus and the back-side bus. In early processors the CPU speed and bus speed (and thus the speed of interactions with memory, etc.) were the same. But a bottleneck (the von Neumann bottleneck) arose because memory speeds cannot keep up with processor speeds. And so accessing the memory was holding the processor back.

15. CSIT 301 (Blum)15 Front-side Bus (FSB) The Front-side Bus (a.k.a. the memory bus or system bus) connects the processor to other parts via the chipset. It allows communication between the processor and main memory (RAM), the system chipset, PCI devices, the AGP card, and other peripheral buses. When the “bus speed” is given as one of the processor’s specs it refers to the front-side bus speed.

16. CSIT 301 (Blum)16 The Northbridge A chipset is a simply group of chips that work together to perform related functions. The Northbridge chipset communicates with the processor (using the FSB) and controls interaction with memory, the PCI bus, and AGP. Northbridge’s partner in the chipset is the Southbridge. The Southbridge handles the IO functions. –The Intel Hub Architecture (IHA) is replacing the Northbridge/Southbridge chipset.

17. CSIT 301 (Blum)17 Backside Bus The back-side bus (a.ka. the cache bus) connects the processor to L2 cache. The term back-side bus is reserved for cases in which the L2 cache is packaged with the microprocessor. –If the L2 cache is separate from the processor, the front- side bus will connect the processor to the Level 2 cache. Cache (SRAM) operates faster than memory (DRAM). The backside bus operates at faster speeds than the front-side bus, sometimes it works at the processor speed.

18. CSIT 301 (Blum)18 FSB Speeds The ratio between the CPU speed and bus speed is a simple fraction. –For example, a CPU speed of 3.2 GHz and bus speed of 800 MHz has a ratio of 4. With Pentium III’s the 100 and 133 MHz FSB speeds became standard. That rate has been somewhat fixed for a few years but what is changing is the amount of data transferred each clock cycle. This is where one begins to talk of “DDR” or “quad-pumped.”

19. CSIT 301 (Blum)19 Edge-triggering

20. CSIT 301 (Blum)20 Edge triggering The clock keeps the various circuit elements working in unison. Elements are typically designed to be active on the “edge” of the clock – either –when it is rising (the positive edge) –Or when it is falling (the negative edge) More precise than level activation, where the action takes places when the clock has a certain state or level (e.g. when the clock is high).

21. CSIT 301 (Blum)21 DDR Double Data Rate (DDR) allows data to be fetched on both the positive and negative edges of the clock. –Thus it is essentially the equivalent of doubling clock rate. –E.g. a 100MHz DDR transfer equals that of a 200MHz SDR transfer

22. CSIT 301 (Blum)22 Quad pumped A quad pumped bus allows four signals to be communicated per clock cycle. This is sometimes called QDR (Quad Data Rate). Pentium 4’s uses a quad pumped FSB. –The 400MHz FSB is a 100MHz bus with four signals per cycle. –The 533MHz FSB is a quad-pumped 133MHz bus. Quad pumping is one of the features of the Pentium 4 Net-Burst micro-architecture.

23. CSIT 301 (Blum)23 Manufacturing Technology

24. CSIT 301 (Blum)24 Manufacturing technology

25. CSIT 301 (Blum)25 Manufacturing technology The next specification found in the table is manufacturing technology, which indicates the size of the components (mainly transistors) which reflects the number of components that can be placed on the chip. In earlier microprocessors, one used terms like large-scale integration (LSI), very large-scale integration (VLSI) and ultra large-scale integration (ULSI). –But as Moore’s Law continued to hold true, we ran out of adjectives.

26. CSIT 301 (Blum)26 Manufacturing Technology Today the manufacturing technology is given in terms of microns or nanometers (e.g. the 0.13- micron or the 90-nm technology). –A nanometer (nm) is a billionth of a meter (10 -9 m). The same chip may be made using different technologies, but this is to done to perfect the newer technology so that more components can be added to latter chips.

27. CSIT 301 (Blum)27 Stepping

28. CSIT 301 (Blum)28 Stepping As with software, mistakes (errata) in hardware are found and revisions are needed. However, hardware mistakes are more difficult to fix. The stepping refers to various fixes, so one wants a higher stepping which presumably has fewer bugs. –AMD uses the term “revision number.” The circuitry cannot be changed on an existing chip, it might be possible to overcome a processor bug by changing the BIOS which can be changed (flashed).

29. CSIT 301 (Blum)29 Pentium 4 Product Information

30. CSIT 301 (Blum)30 Document on Specification Update (Stepping Levels)

31. CSIT 301 (Blum)31 Cache size

32. CSIT 301 (Blum)32 Cache size

33. CSIT 301 (Blum)33 Cache Recall that there are three levels of cache (L1, L2 and L3) associated with the processor. The cache specification on the previous slide refers to L2 cache. A more detailed set of specification will reveal the amount of L1 and L2 as well as the amount of L3 that can be supported.

34. CSIT 301 (Blum)34 Package Type

35. CSIT 301 (Blum)35 Package Type

36. CSIT 301 (Blum)36 Form Factor and Package The term form factor applies to many devices including processors. It refers to their size and shape. And in the case of processors it also includes how they connect to the motherboard. –The motherboard has a slot or socket. A related term is the “package” — an enclosure for a chip (integrated circuit).

37. CSIT 301 (Blum)37 Pinning The pins or leads are how a chip interfaces with the outside world. There are various ways to arrange the pins on a chip. Furthermore, several chips can be brought together into unit called a module (common in memory).

38. CSIT 301 (Blum)38 PGA/DIP/SIP PGA: pin grid array, chip in which the pins are located on the bottom in concentric squares. –Used in some microprocessors. DIP: dual in-line package, rectangular chip with two rows of pins, one on each side. SIP: single in-line package, chip with pins protruding from one side

39. CSIT 301 (Blum)39 SEPP Single-Edge Processor Package With the S.E.P.P. form factor, the processor is not completely covered by the black plastic (as in S.E.C.C.and S.E.C.C.2). The circuit board (substrate) can be seen from the bottom side. An out-dated processor packaging scheme.

40. CSIT 301 (Blum)40 SECC Single Edge Contact Connector With the S.E.C.C. form factor, processors have a plastic shroud covering with an active heatsink and fan. Identifiable by the goldfinger contacts which in this case are inside of the plastic housing. Another out-dated processor packaging scheme.

41. CSIT 301 (Blum)41 Heat Recall that in the history of processors the number of transistors continues to grow (Moore’s Law) while the relative size of the chip stays fixed. With more transistors carrying current, more heat is produced. Various developments have occurred to deal with the issue of heat. One is a reduction in the working voltage (5V  3.3V  2V). Another has been the introduction of the heatsink and fan.

42. CSIT 301 (Blum)42 Heat Sink The computer has had a fan for some time to deal with heat. But starting with the 486, the processor needed special consideration. A heat sink is an element designed to take heat away from the processor. In this case, heat is dissipated mainly via convection, the heat is transferred to the nearby air and is carried away with the air as it moves. –Convection is why a breeze feels nice on a hot summer day.

43. CSIT 301 (Blum)43 Desired Effects A heat sink should have a large surface area since this is where the heat is transferred to the air. But the heat sink should not block the air flow since this is how the heat is carried away. Heat sinks often have very strange shapes to try to maximize these two competing effects. –Typically made of Aluminum –May have “fins”

44. CSIT 301 (Blum)44 Heat Sinks

45. CSIT 301 (Blum)45 Passive and Active All modern processors have a heat sink. Some also require a fan. –Without a fan: passive heat sink –With a fan: active heat sink Because the heat sink’s purpose is to dissipate heat, it is important that the heat can get from the processor to the heat sink. The material “gluing” the heat sink to the processor must conduct heat well. A heat slug is a piece of metal that connects the processor core to the processor package and/or heatsink.

46. CSIT 301 (Blum)46 SECC2 As with SECC, with SECC2 the processors have a plastic housing with an active heatsink (means it has a fan). It is distinct from SECC in that the goldfinger contacts are exposed.

47. CSIT 301 (Blum)47 PPGA Plastic Pin Grid Array With PPGA the processors have pins arranged in a square pattern. They fit into Socket 370 motherboards. Look for the square pattern (Pin Grid Array) on the bottom. Slot connectors do not have pins.

48. CSIT 301 (Blum)48 FC-PGA Flipped-Chip Pin Grid Arrays The chip is designed so that the “core” processor, which is the part that gets the hottest, is on top (closer to the heat sink). Also fits into a socket 370 motherboard. But it must be a FCPGA compliant motherboard for FCPGA processor to work.

49. CSIT 301 (Blum)49 Pentium 4 Form Factors Pentium 4’s also come in a FCPGA form factor. –The package uses 478 pins, which are 2.03 mm long and.32 mm in diameter. FCBGA (Flip Chip Ball Grid Array) –Instead of pins, FCBGA uses small balls, which acts as contacts for the processor. Pins bend, ball don’t. –The package uses 479 balls, which are.78 mm in diameter.

50. CSIT 301 (Blum)50 The LGA "Intel’s new LGA, or Land Grid Array, 775 processor socket takes a step away from traditional implementations in that the package no longer features pins, rather the bottom of the LGA 775 processors only have small gold contacts. With the LGA package, Intel has moved the pins into the bottom portion of the processor socket, something that will make installation of the processor easier in that there is no need to watch for bent pins on the package...although it will make it more difficult as well. You no longer need to worry about bent or damaged pins on the processor, rather now you have to worry twice as much about bent pins within the processor socket itself." http://rootprompt.org/article.php3?article=7115

51. CSIT 301 (Blum)51 References PC Hardware in a Nutshell, Thompson and Thompson http://www.webopedia.com http://www.intel.com http://www.anandtech.com http://www.mbreview.com/lga775.php