If you already have some PC66 SDRAM modules, I would say that it is worth
your while to try them out on a 100mhz bus machine.  It is not at all
unusual for this to be successful.  Your success will depend on the quality
of the PC66 memory.  I am currently running a 32mb SDRAM module that I
bought from Megatrends, before there was such a thing as PC100 memory, on an
ABIT BH6 MB at the 100mhz bus speed.  It even appeared to run fine at the
turbo setting, which I think is about 102.5 mhz.  (No luck at 112 mhz, but I
digress to the OCing thread.)  Admittedly, this was good quality memory and
was rated to run at 100mhz when I bought it, even though it would now be
sold as PC66 memory.

Perhaps others can suggest some ways to make sure that the memory is
dependable at that bus speed, but I would advise running some application in
a loop mode, such as a 3d intensive game.  I used the ZDOPS 3D Winbench 99
test suite and a program that test large numbers to see if they are prime
numbers, called Prime95, to give the CPU and memory a work out.  If you
don't get any error messages and the system doesn't lock up, things would
appear to be working ok.  Of course, if you can't boot into Win95 or 98 to
begin with, you'll have your answer already.

The only danger that I can think of is not to your hardware but to data.  I
am speculating here but I suppose it is possible that you might get some
corrupted data written to your harddrive and not be aware of it, if the
memory almost is working but not reliably.  Again others might be able to
speak more authoritatively on this.

Good luck.

John Sproule


-----Original Message-----
From: Meidling Keith B SSgt <[log in to unmask]>
Date: Wednesday, February 17, 1999 4:22 PM
Subject: 66 Mhz Memory in 100 Mhz Mobo???


>Is it possible/safe to put 66 Mhz SDRAM chips in a 100 Mhz bus Mobo??
>
>I know it probably isn't the best configuration, but can it be done
>safely???
>
>TIA
>

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