RE: OFFTOPIC: SDRAM PC100
On Thursday, June 03, 1999 5:16 AM, E.L. Meijer (Eric)
[SMTP:tgakem@sg10.chem.tue.nl] wrote:
> > > > The question is: if I buy a SDRAM PC100 chip, will it work on a
> > > > computer with bus speed of 66Mhz ?
> > > Nope.
> > Please explain why you think PC100 shouldn't be in a 66MHz board. Do you
> > have any ponters to info on the web?
>
> One thing that may be important to watch out for is that some older
> motherboards need physically different dimms. We have a dual PPro with
> an Intel mobo, which apparently needed special (read: rare) dimms with
> the `nudges' in different places than where they are in the current
> dimms. The current dimms simply don't fit in the mobo.
You hit the issue on the head here. Hopefully I won't screw this up since I
can't find a reference about this on hand, but... PC100 DIMMs are unbuffered
and run at 3.3v and are rated for bus speeds up to 100Mhz (at least they are
SUPPOSED to run at 100Mhz (: ). I personally run them at 66Mhz and 75Mhz on
a couple computers that I have. There is no problem with this: If my stupid
Celery 300A would do it, they would be running at 100Mhz.
There are 2 notches in a DIMM. Each notch has 3 potential positions. The
first one is for buffered vs. unbuffered vs. (I don't know), and the second
one is 3.3v vs. 5.0v vs. (I don't know).
So the original poster needs to check his reference for his mainboard and
see if it accepts 3.3v DIMMs or 5v DIMMs. If it accepts 3.3v unbuffered
DIMMs, then he can purchase PC100 SDRAM and use them at 66Mhz for now, and
later upgrading his mainboard/CPU, he will be able to run them at 100Mhz.
Hope that helps.
Jonathan Lupa
~
jjlupa@jamdata.net
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