Intel Pentium: A Bothersome Bug
The Pentium, introduced in 1993, was interesting for more than one reason. It was the first x86 to drop the traditional model number for a more attractive name, since Intel wasn’t allowed to trademark a name made up of numbers only. It’s also famous because of a bug it contained. On the first generations of Pentiums, certain division operations produced an incorrect result. Intel replaced the processors, but the damage was done. A very rare error gave rise to the first big IT media buzz.
The Pentium was sold in three different versions, the first without a CPU multiplier, the second with a multiplier (including the very familiar Pentium 166), and the last with the SIMD instruction set for x86s, MMX. The Pentium MMX also increased the size of the Level 1 cache and brought in a few minor improvements. This was the first Intel x86 capable of executing two instructions in parallel. The L2 cache was on the motherboard with these processors (running at the frequency of the FSB).
| Code name | P5, P54 | P55 (Pentium MMX) |
| Date released | 1993 | 1997 |
| Architecture | 32 bits | 32 bits |
| Data bus | 64 bits | 64 bits |
| Address bus | 32 bits | 32 bits |
| Maximum memory | 4096 MB | 4096 MB |
| L1 cache | 8 KB + 8 KB | 16 KB + 16 KB |
| L2 cache | Motherboard (FSB frequency) | Motherboard (FSB frequency) |
| Clock frequency | 60-200 MHz | 133-300 MHz |
| FSB | 50-66 MHz | 60-66 MHz |
| FPU | on chip | on chip |
| SIMD | no | MMX |
| Fabrication process | 800-600-350 nm | 350 nm |
| Number of transistors | 3.1-3.3 million | 4.5 million |
| Power consumption | 8-16 W | 4-17 W |
| Voltage | 5 V-3.3 V | 2.8 V |
| Die surface area | 294-163-90 mm² | 141 mm² |
| Connector | Socket 4, 5 or 7 | Socket 7 |
Here’s a little explanation of the Pentium bug: certain calculations using the FPU resulted in erroneous results. This was fairly rare—though sources disagree about exactly how rare—and Intel replaced the defective processors free of charge. Here’s an example of a Pentium error:
4195835.0/3145727.0 = 1.333 820 449 136 241 002 (correct result) 4195835.0/3145727.0 = 1.333 739 068 902 037 589 (incorrect result on a defective Pentium)
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great article with only a few slight errors (like saying the core2duo has 1-4 cores... i don't think there's a 1 cored version lol)
Looking forward to the AMD article.
To correct you. Core 2 Duo has ONLY 2 cores, not more, not less.
Core 2 Quad, has 4 cores and Core Solo has 1 core.
@Arkz
Yes there is a singal core,
http://en.wikipedia.org/wiki/List_ [...] processors
Ok it is not under the same branding but it is part of the same microarchitecture
I might be wrong, but i resemble that the Pentium 166 (32bits adress bus and all) had support for 4Gb of memory. I remember IBM sold it's top line (at that time) with 64Mb support (even with SDR PC100/66 support). Correct me if i'm wrong please.
The core 2 does supply 1-4 cores - 2 cores per die, where one might be disabled, and one or two dies on a socket. It's no less right to call a core2duo a cpu with 1-4 cores, than it is to put the pentium d on the same page as a single core prescot, as it's the very same principle.
great article with only a few slight errors (like saying the core2duo has 1-4 cores http://en.wikipedia.org/wiki/Coree ... i don't think there's a 1 cored version lol)Looking forward to the AMD article.
Thanks for the heads-up! I tweaked that passage to better represent the Core 2 architecture's available configurations!
Ok it is not under the same branding but it is part of the same microarchitecture
Exactly. The article says:
There are many versions of the architecture, resulting in configurations with a different number of cores
There is no mention of the branding, so there is no actual error there, just misinterpretation.
great article with only a few slight errors (like saying the core2duo has 1-4 cores... i don't think there's a 1 cored version lol)Looking forward to the AMD article.
http://www.newegg.com/Product/Prod [...] 6819116039
Yes, it isn't called a "Core 2 Duo," but it uses the Core architecture and only has a single core enabled.
But I will have to say, there aren't any 3 core models...
Good to hear you're not only doing an AMD article, but an ATI one as well (in response to the Nvidia article you did earlier, assuming). A sign of class from the new Tom's is a welcome one.
I wish they would get rid of those stupid SNAP Linkbubless and Inteltex misguiding links. Who ever invented those stupid annoying double lined text popups should have been burned at the stake
What Intelitext do you speak of ? lol (I use a good Hosts file from MVP) blocks most of that crud.
Anyway great article was like a trip down memory lane for me, first Intel CPU I got to use was a 8086 and wow it was slow (I was a kid with ADD give me a break lol) well maybe it was not slow and it was the floppy drive that killed me... Either way best game on it was Qbasic uugghh I think I remember it having CGA with a mighty 4 colors !! I had some paint program for it too.
Compared to Athlon, Pentium 4 is a big loser.
So why is the Pentium 4 "unforgettable"?
My AMD machine (K6 233MHz) smoked all my college buddies Pentium 233s. MatLab, Visio, Quattro Pro, PSPICE, Duke Nukem - everything ran faster on my machine. And it cost me $400 less than the comparable Intel setup.
Just 15? I figure its anything with SX after it, anything Celeron and most of anything HT (hyperthreading heat trap)
oops, my dyslexia read the thing as Most Forgettable.., ignore post above. Maybe thats the next article
Compared to Athlon, Pentium 4 is a big loser. So why is the Pentium 4 "unforgettable"?
Because it was a huge part of CPU history? IDK. Considering that it was not that bad until Prescott, which I am sad they didn't mention.
But the Pentium 4 will always be remembered in my eyes thanks to the Blue Man Group. Them and their crazy stuff.
My AMD machine (K6 233MHz) smoked all my college buddies Pentium 233s. MatLab, Visio, Quattro Pro, PSPICE, Duke Nukem - everything ran faster on my machine. And it cost me $400 less than the comparable Intel setup.
Thats nice. Because this is obviously a competition.
No wait its not. Its just a nice walk down memory lane and they are going to do AMD next so no need for that.
I for one am suprised that they didn't include the Pentium 805. I remember reading how well that one OCed and when OCed it smoked the highest end available and it only cost $150 bucks.
Seriously why bring AMD into this? Its just nice memories not a comparison.
Enjoyed the article, it was a nice walk down memory lane to my teenage nerdhood.
Considering that it was not that bad until Prescott, which I am sad they didn't mention.
If the best you can say about it is "that it was not that bad," that would seem to indicate it wasn't particularly worth remembering.
You forgot the 486DX5 133. Allowed me to up a 486/50 to Pentium 75 performance with just a chip. Worked well till programs started to check for a true Pentium chip before running/installing.
I've got a working luch box with a 386 in it complete with network cards, Working pentium box, a PIII box, the laptop I still use is a P4 3.0Ghz (an hour and half battery life lol), and my new rig has A core 2 duo E8400 OC'd to 4.0Ghz. Good times for me with Intel