Pentium III cC0 Stepping Sspecs

What You Can Reasonably Expect From These Chips

I’m estimating based partly on theory, partly on some preliminary results, that one can probably expect something like 1.0Ghz-1.05Ghz fairly consistently from these chips with high-end air cooling.

By high-end air cooling, I mean Alpha or GlobalWin class. I don’t mean Golden or Chrome or Blue or Fuchsia Orbs. For high-end overclocking, get a high-end cooler.

I don’t understand people who’ll pay $250 for the processor and $200 for a 128Mb stick of RAM, but won’t spend $20 more for a cooler.

You’re likely to be pumping more voltage into a smaller-sized chip to get to 1Ghz or better. Not quite as bad as a Duron or TBird, but getting there. Don’t be penny-wise and pound-foolish.

Two big caveats:

Pretesters have recently been telling me that the overclockability of cB0 chips have declined over the past couple months. It’s unknown whether this will continue to be a problem with cC0 chips.

A lot of you apparently have the notion in your head that you’re going to buy an 800Mhz or 850Mhz, and get an easy overclocking success by running it at 133Mhz.

I think that’s going to be iffy for the 800Mhz, and you probably won’t with the 850Mhz without at least water and likely Peltier cooling. So don’t do that thinking it’s a safe bet; it isn’t. Probably better to buy a 750 and go for a higher FSB overclock.

S-specs for Coppermines with the new cC0 stepping:

100Mhz Processors

FC-PGA Processors  
S SpecSpeedRetail/OEM
SL4CM600EOEM
SL4CK650OEM
SL4CH700OEM
SL4M7700Retail
SL4CF750OEM
SL4M7750Retail
SL4CE800OEM
SL4MA800Retail
SL4CC850OEM
SL4MC850Retail
SECC2 Processors  
SL4C7600E?????
SL4C5650?????
SL4C3700?????
SL4BZ750?????
SL4KF800?????
SL4KH850?????

(????? There’s no indication what these processors are, so I’m leaving them that way for the moment.)

After thinking about this for a while, I’m not going to provide the sspecs for 133Mhz processors.
It doesn’t make sense at this point to buy one if you plan to overclock (that is likely to change with the Coppermine-Ts).

Some of you may be thinking, “Well, I’ll buy an 815 board, and crank it up to 160Mhz or 170Mhz to get my
800EB to 1Ghz. That’s a nice, safe overclock.”

Like hell it is. You’re taking a pretty hefty risk of things not working by running an 815 board at 160Mhz or 170Mhz. Your RAM, even your new PC133 RAM may not work.
More likely, one or more of your PCI devices/hard drives won’t accept the level of PCI overclocking.

Not to say some people can’t get it to work; I know some of
you have. But attempting to do this and buying an EB to make it a safe bet is the overclocker’s version of eating three desserts, then ordering a Diet Coke.

If you want to go for the gusto and try to crank up an 815 board, buy a 650 or 700 chip.

There are two odd items about the EB chips, though:

  1. The SECC2 EB chips at 733Mhz and above usually have a notation, the explanation of which is “Pin AJ3 is removed from these parts.”

    I looked at the Intel datasheets, and there is no pin AJ3. Hmmmm.

    (That notation is also found for the 850, but I think that’s a typo, since that’s the only 100Mhz with that designation; all the others are EB chips).

  2. Far more interesting are the notations on the high-speed Intel chips. They indicate higher voltages, but lower maximum temperatures.

    Most of the chips indicate a maximum temperature of 80C. The 933 and 1Ghz chips indicate a maximum temperature of 70C. The recalled 1.13Ghz chip shows a maximum of 60C.

This means one of two things:

  1. Intel is using a different, more heat-sensitive process for the high-speed PIIS and/or (far more likely

  2. These processors just can’t run at high speeds hot.

If you believe it’s primarily the second, then Intel’s explanation that heat caused the problems with the 1.13Ghz chips makes sense. More importantly, it tells you
what you need to do if you want to get up to that level, cool that sucker as much as possible (and sort of expect to need water/Peltier if you want over 1.1Ghz).

Email Ed


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