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Sharky II

macrumors 65816
Original poster
Jan 6, 2004
1,002
404
United Kingdom
Hi,

I have a 4,1 -> 5,1 with 24GB (3x8GB) of 1333MHz Ram. I know that this is the 'optimal' config for speed as slots 3/4 are shared, etc. I also need low latency performance for audio/sample streaming so the RAM speed and any performance hit is important to me.

However, i'm wondering at what point the 'speed hit' will occur?

For example, if the 4th stick is another 8GB to make up 32GB, will there be a theoretical slowdown once usage goes over 16GB, or is it only if RAM usage goes over 24GB and therefore the last RAM stick is used and is forced to share throughput with slot 3?

I assume that a theoretical slowdown would appear as soon as you over over 16GB RAM usage, because otherwise there's no downside to going to 32GB - if you go over 24GB and all you have is 24GB you page out to HD, and that's much slower than any speed hit you'll get from sharing slots 3 and 4.

Is this correct? Or does it not work like this at all?

Thanks,

Ed
 
Last edited:
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