🚀 go-pugleaf

In article <1868@ddbeano.Dundee.NCR.COM>, stan@ddbeano.Dundee.NCR.COM writes:
> In article <1993Jan8.100550.9995@ac.dal.ca>
> francis@ac.dal.ca writes:
> 
> > I have a 486DX/33MHz system, and I have been told by the manufacturer 
> that
> > the motherboard is upgradeable to 50MHz by plugging in a new crystal and 
> CPU.
> > 
> > Question:       Is it possible to plug in (say) a 40MHz or even a 50MHz 
> crystal
> >                 into the board *without* replacing the old (33MHz) CPU? 
> > If so, is there a performance improvement or will the 486DX 33MHz chip 
> just
> > burn itself out, ie, has it been internally hardwired for the specified 
> clock
> > frequency of 33MHz?  I would like to hear from anyone who has attempted 
> this
> > (with/without success).
> > 
> I increased a 486sx25 to 40Mhz by adding a heatsink and fan. No problems.
> 
> Stan


Some manufactures are in fact selling 33MHz Intel CPUs with a 40MHz clock.  I
would not trust it though.  If the CPUs were stable at that sort of speed, then
Intel would have sold them at that sort of speed.

If you do intend to try it, and your old clock is 33MHz, you will probably find
that the crystal unit is actually 66MHz, the speed of the crystal unit is divided
by 2.  So if you put in a 40MHz unit, your board will divide it down to 20MHz. 
There is probably a jumper to turn the divide by 2 off.

If you do try it, fit a heatsink to the CPU and keep an eye on the temp of the
CPU.  Let me know how you get on.

Mark


-- 
Mark 
______________________________________________________________________________
mark@uk.ac.ox.physchem