On 29 Mar 98 at 22:53, Trumpet286 wrote:

>   I'm running a 486sx I was wondering what was the best way to
> increase clock speed, it is running at 33 Mhz right now.  Any
> suggestions will be great.

  There are two basic possibilities:

1.  Your 486SX is in a socket (preferably Socket 3, since that makes
removal easier, using the release lever on one side).  Your
motherboard should accept almost any DX2 chip directly, although best
results will be obtained with an OverDrive (but OverPriced) model.
[There are various flavours of DX2, and your motherboard may only
support some of them.  The OverDrive is designed to work with older
motherboards.]
  You could also go to a DX4 or 5x86; these are 3v CPUs, and if your
motherboard doesn't provide a switch between 5v and 3v, you'll also
need a voltage regulator, either purchased separately (I think
PowerLeap still sells them) or bundled with the chip (Kingston,
Evergreen, Intel *OverDrive* DX4).  These generally include a nice
big heatsink -- you definitely want more cooling on such a CPU, even
with its lowered voltage.

2.  Your 486SX may be soldered to the motherboard.  If so, your
motherboard maker should have taken Intel's recommendation to add an
OverDrive socket.  If you have a 487SX installed, that's where it
would be.
  In theory, almost any of the options listed above can be installed
in that socket.  In practice, Intel non-OverDrive DX2 and DX4 chips
may lack the pin that tells the soldered-in CPU to step aside and let
the new chip run the show.


  If your motherboard was designed specifically for the SX, there may
not be any L2 cache provided.  Installing a 2x, 3x, or 4x CPU may not
noticably improve performance without such a cache, since main RAM
will still only be running at 33 MHz.


  You'll be lucky to get a solid doubling of system speed for $100 or
so.  I recently bought a P133 and a pretty decent motherboard for
about $120, so unless you have a lot of VLB peripherals and/or 30-pin
SIMMs, upgrading to a Pentium system may be a better investment than
trying to speed up your 486.


David G