Thursday, December 31, 2009

Why AMD's processors known to create more heat than Intel's (and why AMD cheaper than Intel) ?

AMD and Intel Logo


Please keep it in mind that this note is my personal conclusion from a simple and unofficial online research I've done. This note is not the correct and validated source of info. I'm not attached to either AMD or Intel in any way. Thanks.


All source from :
A little bit of a background story :
In the early 1980s, AMD provided the 8088 and 286 class processors as an Intel licensed alternative source. When the 386 class processors came out, Intel decided to break off its agreement with AMD and the two companies starts one of the biggest rivalry in the history of technology business. AMD eventually produced 386 and 486 class microprocessors that were derived from Intel's designs through reverse engineering.

Starting with the Pentium generation, AMD shifted its design strategy. AMD began creating its own original processor design for the K5. The K5 runs the same software as Intel's Pentium and plugs into the same socket, but internally the design is entirely different from Intel's.

Because it was AMD's first experience with an independent x86 design, it made AMD longer than planned to get the K5 into production. AMD underestimated the difficulty of creating an independent design and made some bad design choices. As a result, the K5 was late to market. When it did arrive, it was slower than expected. After a major revision, AMD was able to boost the chip's performance considerably. But Intel's mainstream chips got much faster in the meantime.

Since the competition between AMD and Intel still largely dominated by Intel, AMD had to take a few strategic decisions. Two of them are the decision to purchase a microprocessor company named NexGen, and to build a new processor manufacturing facilities named Fab 25 in 1996. Little did people know, although the name K6 seems like a continuity from K5 series processor, design-wise its very much different. K6 manufacturing process is the first experience of AMD in producing processor at 350nm/0.35µm production process.

The new facilities is dedicated to producing x86 microprocessors and controlled by team from NexGen. AMD needs to keep this facilities output full to justify its investment, and this leads to aggressive pricing of the K6. Furthermore, since AMD is highly motivated to gain market share, it is willing to accept a much smaller profit margin than Intel. AMD has vowed to keep their prices 25% below Intel’s. So far, they have kept that promise. So far, AMD managed to kept their promise.

Quick Facts

[ AMD K6 VCore comparison with Intel Pentium II ]

AMD K6 (released 1997)
    Series :
  • AMD K6 (model 6) = VCore 2.9V/3.2V/3.3V

  • AMD K6 "Little Foot" (Model 7) = VCore 2.2 V

Intel Pentium II (released 1997)
    Series :
  • Intel Pentium II (Klamath) = VCore 2.8V

  • Intel Pentium II (Deschutes) = VCore 2.0V

  • Intel Pentium II Mobile (Tonga) = VCore 1.6V

  • Intel Pentium II Mobile (Dixon) = VCore 1.5V/1.55V/1.6V/2.0V

----------------------------------------------------
[ AMD K6-2 VCore comparison with Intel Pentium III ]

AMD K6-2 (released 1998)
    Series :
  • AMD K6-2 (Chomper) = VCore 2.2V

  • K6-2 (Chomper Extended) = VCore 2.0V/2.2V/2.3V/2.4V

  • K6-2+ (Mobile) = VCore 2.0V

  • AMD K6-III (Sharptooth) = VCore 2.2V/2.4V

  • AMD K6-IIIP = VCore 2.0V/2.2V

  • AMD K6-III+ = VCore 1.6V/1.8V/2.0V

Intel Pentium III (released 1999)
    Series :
  • Intel Pentium III (Katmai) = VCore 2.0V/2.05V

  • Intel Pentium III (Coppermine) = VCore 1.6V/1.65V/1.7V/1.76V

  • Intel Pentium III (Coppermine-T) = VCore 1.75V

  • Intel Pentium III (Tualatin) = VCore 1.4V/1.475V

For my analysis, I chose AMD K6 (model 6) and Intel Pentium II (Klamath) as the samples of all AMD K6 and Intel Pentium II series processor
  • AMD K6 (model 6) Specification :

  • > Total Transistors : 8.8 million
    > Production Process : 350 nm/0.35µm
    > L1-Cache : 32 + 32 KB (Data + Instructions)
    > Instructions Set : MMX
    > FSB : 66 MHz
    > VCore : 2.9 V (for 166/200MHz clockspeed variant) 3.2/3.3 V (for 233MHz clockspeed variant)
    > Clockspeed Variants : 166, 200, 233 MHz
    > Die Size : 162mm²
  • Intel Pentium II (Klamath) Specification :

  • > Total Transistors : 7.5 million
    > Production Process : 350 nm/0.35µm
    > L1-Cache : 16 + 16 KB (Data + Instructions)
    > L2-Cache : 512KB (with 512MB cacheable)
    > Instructions Set : MMX
    > FSB : 66 MHz
    > VCore : 2.8 V (for all clockspeed variant)
    > Clockspeed Variants : 233, 266, 300 MHz
    > Die Size : 203mm²
My Analysis
    When I compare those two samples processors, I noticed a few significant facts that I listed below :
  • Both processors had gone through the same production process (350 nm/0.35µm)

  • AMD is less experienced with 350 nm/0.35µm production process

  • Intel is more experienced with 350 nm/0.35µm production process

  • Both processors had the same FSB speed (66MHz)

  • AMD's processors die size is smaller (162mm²) than Intel's (203mm²)

  • AMD's processors had more transistors (8.8 million) than Intel's (7.5 million)

  • AMD implemented different VCore for each of its processors' clockspeed variants

  • Intel implemented the same VCore for all of its processors' clockspeed variants

  • There is a possibility that both AMD and Intel has different quality of materials

  • Both AMD and Intel had different internal design (although at some point they might be similar to each other

My Conclusion:

It is no doubt that AMD and Intel would have different internal design of their processors variant. The lack of experienced might also contribute to the final result of the processors that AMD produced. Since the obvious fact that AMD is really eager to "beaten" Intel's domination in the processor's market, AMD seems to be to rushed their processors' designs line up into production, thus affected the quality of their processors.

Technically speaking, AMD designed their processor in 162mm² die size, which is considerably smaller than Intel's (which is 203mm²). Despite its smaller die size, AMD had put more transistors into their processors (8.8 million) while Intel only has 7.5 million transistors. It is possible that the reason why AMD K6 processors producing more heat is because of the higher voltage. AMD K6 processors need higher voltage because it has more transistors than Intel Pentium II processors. Another possible reason is that AMD K6 processors has lesser "free space" compared to Intel. Because of that, the heat produced by AMD processors while operating is likely to be more concentrated than Intel's processors. If I'm not mistaken, I've read somewhere that AMD processors usually has lower Thermal Design Power (TDP) than Intel's processors.

As for the matter why AMD processors are known to be cheaper than Intel, you can easily interprets the answer by reading the background story at the beginning of this note.

If you had different opinions or wanted to state my mistakes, please do so.
Thanks for reading!