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jparisi · May 28, 2003, 10:43 AM

Can I do this or is it a no-no?

OldManMac · May 28, 2003, 10:54 AM

Yes, it will just run at the 100Mhz bus speed.

bradoesch · May 28, 2003, 06:30 PM

I have 133 MHz SDRAM in my 100 MHz bus iMac and it's working fine. I have read about 133 MHz RAM that won't slow down to 66 MHz (or maybe it was 100 MHz?), so you might want to make sure you can return it if doesn't work.

drcarl · May 29, 2003, 01:06 AM

I think Apple actually recommends using 133 on 100Mhz bus iMacs (at least the FP iMacs).

tooki · May 31, 2003, 02:13 PM

The speed rating (PC133/100/66) is a maximum. It will function fine at the lower speed.

The only consideration is that at the same time clock speeds increased, so did chip densities, so some high-capacity modules aren't properly recognized by older computers. (E.g. some PC100 Macs like my blue G3 can't use 512MB modules.)

tooki