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tampano

macrumors member
Original poster
Feb 15, 2016
49
3
Hello,
i'm moving from a single processor tray with a X5680 where I have 64GB of RAM (4x16) to a dual processor tray where i'll replace the two E5620 with two X5680. What's the maximum memory for the dual tray with those processors. And...is there a better configuration than the maximum amount of RAM? I randomly read about the bus speed with less memory channels occupied but I confess I forgot the principle around it.
Thanks.
 

flowrider

macrumors 604
Nov 23, 2012
7,323
3,003
TinyGrab Screen Shot 4-23-20, 6.47.40 PM.png


Lot's written about that on this forum. The CPUs are three channel and filling slots 1-3 and 5-7 provide the optimum, as far as speed goes, configuration.

Lou
 
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h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Hello,
i'm moving from a single processor tray with a X5680 where I have 64GB of RAM (4x16) to a dual processor tray where i'll replace the two E5620 with two X5680. What's the maximum memory for the dual tray with those processors. And...is there a better configuration than the maximum amount of RAM? I randomly read about the bus speed with less memory channels occupied but I confess I forgot the principle around it.
Thanks.
Depends on your usage

For Linux / Windows, you can boot 8x32GB = 256GB RAM

For Yosemite, max at 5x32GB = 160GB

For newer macOS, 8x16GB is the max = 128GB

In general, install as much as you can is the best. Unless your main workflow is to run benchmark.

That triple channel thing makes almost no difference in real world. Benchmarking software disabled hardware cache, in real world, no one will disable hardware cache. Therefore, the real working speed is pretty much the same.

However, more available RAM means the OS can store more data in the idle RAM as cache (software), reduce the requirement to read the same data from hard drive again. That can speed up the whole computer. Having NVMe etc can reduce the gap, but "read from NVMe" still can't be faster than "the data already stored inside the RAM".

But if you believe 96GB is good enough, then it's nothing wrong about it. IMO, as long as no SWAP require, your memory config is good.
 
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