Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror
×
Hardware

Overclocking Pentium IIs 60

Dr. Damage writes "Ars Technica has just published an article entitled Clocking and locking the Pentium II. The article looks at exactly how PCs generate and control CPU clock speeds and how Intel locked the bus multiplier in the PII. It's also got some tech explanations and speculation about the possibilities for bus locking the PII/PIII architecture to prevent overclocking. "
This discussion has been archived. No new comments can be posted.

Overclocking Pentium IIs

Comments Filter:
  • Posted by Mr. Assembly:

    The mips line of processors is going to die! SGI is going to move to intel, so your going to be pissing on your own computer anyway. Just be sure to have the paper towels handy to cleanup.
  • Posted by Mr. Assembly:

    By the time that the components burn out if they do you're going to be tossing everything for an uprgade anyway. After three months your computer has devalued to nothing to even give this a passing thought. You know, I bet your the kind of guy that does'nt rip the tags off your pillows either, huh? I bet I'm right.
  • Posted by Tax_cheat_and_d_FBI_is_after_me:

    I hate both INtel and Microsoft

    their both make shit stuff,
    G3 or any other RISC chips are way advance,

    go 64bit UNIX !
  • "Intel has a pretty sane way of providing the consumer some protection against buying remarked, overclocked Xeons. Each Xeon has a processor information ROM (PIROM) built into the processor substrate. This PIROM is electrically programmed at the factory to hold details about the chip's core type, core stepping, etc. There are 16 bits at offset 16h in the PIROM that store the processors maximum core frequency (in MHz). So if you want to know what the speed your Xeon was rated at, just check that number.

    It seems to me that if Intel is as serious about stopping illegal overclocking as they are about robbing every last shred of privacy from their customers, then they'd just do something like this
    with the PIII, instead of that ridiculous CPU serial number"

    --
  • >Just let everyone burn up their chips trying to o/c above spec

    I've heard of plenty of people trying to overclock chips, and never heard *anyone* say they burned out a chip doing so.

    Do you just hate the thought that somebody out there may be getting the same performance as you for less?
  • >Intel actually already pushes their chips to max safe speed so that they can make the most money.

    Just to explain a little economics, this isn't how things work.

    Suppose Intel made one chip at one speed; how would they price it? Price it high, and only richer people buy it. Price it low, and those who would pay premium prices will pay the low price. It's much better to have more than one product, so you can sell the better product at the higher price and the worse one at a lower price -- you maximize your earnings. And if you only have one real product (how does a 350 mhz Pentium II made to 0.25 micron process differ from a 450 made on that same process?), simply sell some as a lesser product.

    This is by no means unique to Intel or even the computer hardware market. In software, Autodesk sells AutoCAD for ~$5000, AutoCAD Lt for ~$350. Does it cost Autodesk more to produce and support AutoCAD? Not really, not significantly; in fact their production costs would probably be lower with a single product. But there's no way they could sell AutoCAD for $5000 to some people and $350 to others (save things like academic sales.)

    Nor for that matter is this unique to the computer industry. You'll find clothing companies have different lines, with trivial differences, but one has the marquee name and the other doesn't. Ditto shampoos, soaps, TVs, you name it.
  • Bah!

    Real men use MIPS. ;>

  • by mholve ( 1101 )
    Yeah, but it'd be a fast, ugly POS! Hehehe.

    I digress, and agree.

  • If you're gonna use that Windoze shit, you need all the speed you can get. Sorry buddy.
  • "PIIs are already run hotter than any chip out there. Hell. I'll put money on the fact that in
    a couple of years, people with PIIs will:
    1. have to buy new motherboards to support the PIII or P4.
    2. have to junk their system cause the chip is fried out. "

    1. I read somewhere that the core voltage requirement of the PIII (really just a PII with KNI) is such that a PII mobo won't support it.
    2. Hasn't this been the standard in the Intel world for years?

    "I could put a rocket engine on a Yugo and it would go faster than any other car out there, but it'd still be a
    p.o.s."

    You can't polish a turd.

  • " Intel actually already pushes their chips to max safe speed so that they can make the most money"

    This is a false assumption.
    Intel actually takes chips rated for 450, and marks them as 300, because they need to justify a lower price-point to compete with AMD on the low-end. That was the whole point of the Celeron line, if you recall the original Celeron, it had NO cache, and sucked. The new Celeron has on-die cache, and is no different from the PII you would spend $300 on.

    If a smart enduser can figure out how to squeeze his cut-rate 300 to 450, and screw intel in the process, then more power to them.
  • Um didn't SGI (PackardBell wannabes) just sell off their interest in MIPS?

    Didn't SGI (Gateway wannabes) just introduce a new line of Intel-NT based workstations?

    bub-bye IRIX.
    bub-bye MIPS.
  • The article explains why it's unfeasible for the CPU to have a frequency detector on-board. Re-read it.
    --
    Kevin Doherty
    kdoherty+slashdot@jurai.net
  • Poor guy probably hasn't gotten his chip to OC.
  • to do this, i have opened the black plastic box, remove the PCB of my p2, then i drilled the 4 rivets of the metal plate... i then replace some thermal paste, reput PCB etc, and i put my big heatsink and fan on it!

    also i never reput the black plastic box, my p2 is cooler without it... the retention is done by the heatsink
    --

  • Why couldn't Intel just create a pointer or CPU Hardware marker that when a processor is overclocked it will be marked (hardware) that it has been pushed passed it's spec. THat way when it was returned for warranty it would be checked and refused or vice-versa. If we keep burning them out we will also keep buying them. I currently have a Celeron 300A runing very nicely at 450Mhz@2.0V and have not even had a burp..
  • Why am I an Idiot? I got a Pentium II 450Mhz computer for around $400 less than buying the legit 450 PII. And by the way how did I void the warranty of the components in my computer...how the hell is the manufacturer of the rest of my stuuf going to know I overclocked it. Think about what you say before opening your mouth....
  • Some of this is true. At some point, Intel will mark chips at their maximum "tested" speed.

    But think about it.. after Intel gets to 0.25 micron, and they're making Xeons and PIIIs... do you REALLY think that they're still having trouble getting Celerons to be stable at 300?

    Part of the reason they make different speeds at different prices is just that - they need multiple price points. It's marketing. Far enough into production of a chip, odds are most EVERYTHING runs at top speed, but they mark it "300" because they need something they can sell for under $100.

    I'm also curious to know how someone will find out I overclocked a machine... sheesh.

    So do you like working for Intel? How long have you been there? :)
  • The PLL is not complete. Yes, there can be a multipler that is on the output of the vco. Generally, there is ALSO a multiplier/divider on the feedback loop leading from the VCO to the comparator. Setting this to some frequency division, and you have an output clock that is higher than the input clock.

    (yes, that is right. You divide to increase the clock).

    Clock dividers are a lot easier to design, so I wonder why this article used a clock multiplier.
  • It takes a real man to underclock them.

    I've got a K6-2 350Mhz running at 300Mhz.

    Call me crazy.



  • If anyone remembers it the IBM PC was clocked at a scorching 4.77 MHz.

    Well, actually, I believe they did this so that they could drive the TV output of the same clock crystal as the processor . . .

  • My warantees, my hardware, my problem, not yours.
    'nuff said
  • Thank you for educating me FUDmeister.

    I guess I should buy a Packard Bell and never, ever, break that little hologram sticker on the case. It voids your warranty, you know. And I certainly wouldn't want to do something that the manufacturer didn't intend.

    Gasp! I've heard that some really bad people out there actually RECOMPILE their operating systems. Those idiots! Don't they know that if they make a mistake, their computers will blow up and they won't be able to use chatrooms any more??
  • Like my PS/2 Model P75. I have to watercool the silly thing because the CPU in it has too *high* a rating. It just won't run at 33 megahertz without cooling, and 25 megahertz is--well--unbearable. (I use this thing mostly for nostalgia's sake anyway.)

    (The watercooling is ugly; it involves plastic sandwich bags filled with water and closed off with a rubbish bag tie (you know, the little metal wires embedded in papaer). I used several layers of saran wrap to protect the thin water filled bags against the sharp edges of the electronic componentry on the option adapters above the CPU. This should give you an idea of just how old these option adapters are; they still have soldered pins sticking through, unlike newer (i.e. almost anything made since 1988) PC boards where the pins don't reach through the whole plastic card.)

    One disadvantage is that my IBM Portable PS/2 is no longer portable at all. It is rather a quivering mass of digital protoplasm on a lab shelf.

    Cheers,
    Joshua (who is looking for an 80 megahertz oscillator. Gee, if I can ``underclock'' 33mHz, why not 40mHz?)

  • *eep!* argh, you dirty mouthed people actually got me post! I'm so embarressed.

    What kind of people are you? I certainly don't go around calling people a 'dolt' or a 'stupid fucker' esp in public just because they happened to be mistaken on something. C'mon people, we geeks can be more civilized than that.

    deimos@kfa.cx
  • HOLY COW! I posted again! /me hides in the corner chargrined...
  • PIIs are already run hotter than any chip out there. Hell. I'll put money on the fact that in
    a couple of years, people with PIIs will:
    1. have to buy new motherboards to support the PIII or P4.
    2. have to junk their system cause the chip is fried out.

    okay folks:
    I could put a rocket engine on a Yugo and it would go faster than any other car out there, but it'd still be a p.o.s.
  • Just let everyone burn up their chips trying to o/c above spec and that way, they will buy more intel chips ... o/c TOO much, burn it up...buy more intel chips...etc etc
  • Will a chip burst into flames from excessive overclocking? Probably not.

    But it will suffer from a major "meltdown" when clocked too high (and therefore run too hot). I know people who have wrecked chips, and even motherboards, doing this.

    And Intel, along with keeping the unscrupulous resellers at bay, locked its chips to keep anyone in the know from telling the cattle that the Pxxx's were already out for cheap.

"Most of us, when all is said and done, like what we like and make up reasons for it afterwards." -- Soren F. Petersen

Working...