My first PC ran on an AMD AthlonXP 1700+. It had a Palomino core running at 1.43Ghz, a 266MHz front side bus, and 256KB of L2 cache. But that wasn’t what started my infatuation with technology. That was due to my friend’s Pentium 1 133mhz and Voodoo graphics card. Back then, playing StarCraft, Theme Hospital, and The Settlers 2 til the early hours of the morning was a common occurrence.
While a thorough history of CPUs is beyond the scope of this article, let’s take a look at a few titbits of the industry that brought us to where we are today.
CPUs have come a long way since the 2300 transistor, 740kHz, 4-bit Intel 4004 was released in 1971. At the time, AMD was just a maker of logic chips.
It wasn’t until 8086 that Intel introduced the x86 architecture that we all love (and sometimes hate). It was the 8088 that was used in the IBM PC though, running at 4.77MHz with 16KB to 256KB of RAM. Then, on the 12th of August, 1981, The IBM PC 5150 was released. From its use of (mostly) off-the-shelf components, an open architecture, and the release of the IBM PC Technical Reference Manual, many cheap clones soon began to enter the market. The 5150 did not come standard with a HDD, but prospective buyers had the option of either a floppy disk or cassette system.
In 1991, Intel then released the first 32-bit x86 processor, the Intel 386DX, which AMD soon reverse-engineered and named the Am386. The Am386 reached higher clock speeds than Intel’s 386, at 40MHz and 33MHz respectively. Rather startlingly, a 40MHz Am386 armed with a 40MHz 387 Math co-processor would outperform even Intel’s new and expensive 486 platform.
Next, we have the renowned Pentium processor. Its 3.1 million transistors ran at a blisteringly-fast 60MHz on a 0.8µm process, and boasted a 50MHz FSB. The Pentium had a few improvements over the 486, including the ability to complete more than one instruction per clock cycle. However, the processor suffered from a bug in its floating point unit that caused errors while performing certain floating point division calculations. Perhaps ironically, the media furore surrounding this bug, combined with Intel’s “Intel Inside” marketing campaign, soon made Intel a household name.
Fast-forward to 1999: AMD becomes the first CPU manufacturer to break the 1GHz barrier with their K7 Athlon. With the Athlon 64, AMD let the aging front side bus fall to the wayside in favour of Hypertransport. The Athlon 64 also brought with it 64-bit extensions for the x86 instruction set (called x86-64) which allowed full backwards compatibility with existing 32-bit applications. This implementation differed radically from Intel’s 64-bit implementation (IA-64) in the Itanium, which had poor x86 32-bit performance. Eventually, Intel incorporated AMD’s instructions under the name EM64T.
In 2000, Intel released the Pentium 4 which used the infamous RAMBUS RAM, which they later switched for SDR, then DDR. The Netburst architecture was supposed to scale to 10GHz, but I suppose Intel decided that having multiple suns in our solar system was a bad idea.
That’s where we’ll stop for now. In the next article, we’ll have a look at the processors currently on the market.