🚀 go-pugleaf

Craig,

I have been overclocking my Intel DX2/66 since I bought it some time ago, and never have
had so much of a hiccup in DOS|LINUX|WINDOWS|OS2.  I do use a heat sink, with plenty
of heat sink compound and a cpu fan.  Be advised that other things in your system may need
to be adjusted:

1) AT BUS speed.  This is often provisioned in the BIOS as a ratio of the systen bus speed.
   Therefore, if you up the system clock to 40 you may clock the AT bus too high, especially
   if, like me, you were pushing it to begin with!

  Signs that you may have the AT bus speed set to high:
   Problems with reading or writing to floppy disks.
   Missing or scrambled characters on ISA bus video cards.
   To fix: If option is in your BIOS increase the ratio of AT/SYSTEM bus speeds.
   For example:  If you have a DX2/66 your ration is probably set by the dealer
                          as CLOCK/4    33/4 ~= 8.3 whatever which is AT bus speed spec.
                          Increasing CLOCK to 40 would raise it to 10 ( which most equipment 
                          now 'days can handle anyway. You get the picture.
   

2) Memory read and write wait states ( both DRAM and SRAM ).  Often when pushing your
    system to a higher rate ( such as 40 MHZ ) you may need to interject more wait states into
   your memory read and writes.  But this is dependent upon your system.

  Signs you need to add wait states: ( Things that may happen after overclocking )
  Memory Parity errors ( especially in windows )
  Failing HIMEM memory check at boot up.
  Failure of tests in things such as Norton utilities.
  Without exception I have been able to remedy these by adding wait states as necessary.

3) If you have VESA cards, make sure they can handle a >33 MHz clock.  Many cheap ones
    don't and are the bane of the folks who bought the original DX-50 chips.

I have set up overclocked systems for many of my friends, and have never had an obstacle that
I could not overcome.  With the rapid obsolescence of these chips, ( I mean, really, how long are you
going to use that chip, 2 years? ) the possibility of slightly shortening the life of the processor  
isn't really an issue compared with getting the extra uumph out of the thing in my opinion.

If you have any more questions about this, let me know


In article <1994Dec8.115529.3574@muffin.pronet.com>, cas@muffin.pronet.com (Craig Sanders) writes:
|> 
|> I just got myself a dx2-66 overdrive cpu and plugged it into my
|> motherboard.  After a few initial problems (operator error) it works
|> very nicely at 66Mhz.
|> 
|> I was really surprised at how cool the thing is running, though.
|> Everything I had read and been told indicated that the chip would be too
|> hot to touch.  I can touch the chip and it's barely warm...doesn't even
|> come close to burning my skin.
|> 
|> (my father, who bought a dx2-66 overdrive at the same time runs DOS &
|> Windows and tells me that his CPU is burning hot - he can't even touch
|> it for a few seconds whereas I could leave my finger firmly pressed onto
|> mine for minutes without feeling more than warm)
|> 
|> 
|> I guess Linux must be really kind to processors because it uses the HLT
|> instruction to idle, rather than sitting in an idle loop.
|> 
|> Anyway, this brings me to my question.  The overdrive chip has got a
|> heatsink stuck on top of it, which prevents me from sticking the CPU
|> fan I bought onto it.  This concerns me a bit because I was thinking of
|> running it as a DX2-80.
|> 
|> Has anyone had any experience running an overclocked DX2-66 with Linux?
|> Given that the chip runs so much cooler than under Dos or Windows, is it
|> relatively safe to just run it at 40MHz without the CPU fan?
|> 
|> 
|> -- 
|> cas@muffin.apana.org.au
|> 
|>     "Organise a strike in your school or workplace on the grounds that it
|>      does not satisfy your need for indolence & spiritual beauty."
|>                               -- Hakim Bey, The Temporary Autonomous Zone
|> 

-- 

Nathan Bond                        Alcatel Network Systems
nbond@rockdal.aud.alcatel.com      Richardson, Tx