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Mixing Ram Speeds

About a month ago I bought 512megs of PC 100 ram for my G4 450 and when it came they sent me PC 133 not PC 100. When I called they told me it was ok to mix 100 and 133. I got differing opinions about whether this was ok. Is it? I'v e been getting some strange stutters on certain programs since then. Mostly on Audiodesk. Could mixing up the ram be the cause?
Thanks
[376 byte] By [trick fall] at [2007-11-15 10:04:37]
# 1 Re: Mixing Ram Speeds
PC133 works fine in older PC100 Macs.

That was easy.

And here I thought you were gonna ask about CAS 2-2-2 versus 3, etc latency. Whew! :)
Brad at 2007-11-17 15:53:16 >
# 2 Re: Mixing Ram Speeds
Thanks, one last question....should I put the 133 in the first slot? Does it matter?
trick fall at 2007-11-17 15:54:16 >
# 3 Re: Mixing Ram Speeds
Doesn't matter. You know that the 133 will run at 100 right? It's the clock on the board that runs the chip. If the board is 100 then the RAM runs at 100.
Scott_H at 2007-11-17 15:55:14 >
# 4 Re: Mixing Ram Speeds
i believe you should put the slowest/smallest Dimm in the first slot 0-1 followed by the others.
oh and for latency, say the first DIMM is 3-2-2 and the others 2-2-2 you need to put the 3-2-2 one first to assure stability

[ 12-08-2001: Message edited by: Gigawire ]</p>
Gigawire at 2007-11-17 15:56:19 >
# 5 Re: Mixing Ram Speeds
Care to explain why? I've never heard that it matters... I'm interested.

-Ender
Ender at 2007-11-17 15:57:18 >
# 6 Re: Mixing Ram Speeds
I had that happen too, I bought three PC100 512 MB chips and they were all PC133 when I got them. http://www.sevensquareinches.com/graphitesmilies/rolleyes.gif
Logan Cale at 2007-11-17 15:58:17 >
# 7 Re: Mixing Ram Speeds
for pc's the dimm in bank 0-1 is poled for its configuration, that configuration is then applied to each bank. Newer mainboards (1 yr old or so)have manual options for each bank. So if i put cas 2-2-2 ram in bank 0-1 and 3-2-2,3-3-3, etc in the others, the comp will read all banks as 2-2-2 and run accordingly, thus creating stability issues. The same applies for RAM speed.
Gigawire at 2007-11-17 15:59:21 >
# 8 Re: Mixing Ram Speeds
All 3-2-2 and 3-3-3 PC133 RAM will be read as PC100 2-2-2 on Sawtooth machines.
Leonis at 2007-11-17 16:00:24 >
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