DRAM Clock Ratio question

I'm playing around with OC ing my P4 -2.4 533 fsb. in an MSI 645E board. It
has 1.5 gig of generic PC-2100 ram. I had it running at fsb155 but had to
set the DRAM clock ratio down to 232. It was either that or let it go way
over the stock 266. My question is about the "by SPD" setting. I presume
that it is an auto setting by the guts of the chip. If one OCs and sets it
to the by SPD, will it keep the ram at 266 or will it also get OCed as the
FSB gets jacked up? Also,is over all performance, if a 2.4 is running OCed
at say 2.6 or so with the ram underclocked at 233 or so, going to be better
or worse? Just how much difference does the speed setting of the ram make?
Thanks

Scratch the first part of that question. I see now that once you change the
FSB from stock or auto to something else, the "by SPD" option is no longer a
choice. Still wonder about the jacking up of the FSB and lowering the ram
speed to be able to do it.

"Forrest" wrote in message
...
I'm playing around with OC ing my P4 -2.4 533 fsb. in an MSI 645E board.
It
has 1.5 gig of generic PC-2100 ram. I had it running at fsb155 but had to
set the DRAM clock ratio down to 232. It was either that or let it go way
over the stock 266. My question is about the "by SPD" setting. I presume
that it is an auto setting by the guts of the chip. If one OCs and sets it
to the by SPD, will it keep the ram at 266 or will it also get OCed as the
FSB gets jacked up? Also,is over all performance, if a 2.4 is running OCed
at say 2.6 or so with the ram underclocked at 233 or so, going to be
better
or worse? Just how much difference does the speed setting of the ram make?
Thanks