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Dual socket CPU's and their RAM

So I feel like this may be a bit of a dumb question but…I’ve been thinking about buying a dual-socket 2011 -v3 board and it occurred to me if you have two sockets and two sets of RAM slots does that mean if I want 32 GB of RAM for the system does that mean I need to have a total of 64 GB, 32 for one CPU and 32 for the other ? I’m sorry for the noobish question, but I’ve been building regular single socket systems for a while now and this hasn’t really come up.

No, putting 64 gb of ram in the system will give you 64gb useable, just like a single socket system.

Each CPU does control half of the ram, so if you have only one CPU installed in a dual socket board then normally only half of the RAM slots will work. Also, there is a latency penalty for accessing information from ram controlled by the other CPU then the program is running on.

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For best performance you will want one RAM stick per channel on each CPU.
So for four channels on each CPU you want 8 4 GB sticks.

It is not like with SLI video cards. With video cards each card can only read its own RAM so it needs a copy on each card. That means that for video cards two cards with 4 GB each still only have effectively 4 GB.

With CPUs each CPU can read RAM connected to the other CPUs. So 32 GB as 16 GB on each CPU is a full 32 GB.

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The other guys above covered it. However if you’re “thinking about” it, then be aware that NUMA causes performance issues with various applications.

If its cheap and for shits and giggles - go for it. But if you’re doing this for performance reasons you may want to consider a new AM4 system (or even a new X299 box) to get the same sort of core count and no NUMA problems for similar/less money.

Well I am an IT student and I just think I want something to tinker around on/ it would replace my current unraid build which is a Z270 w/7600K it’s nice and all good single threaded performance but with only 4 threads sometimes i feel a bit limited.

I rip my bluray’s and then encode them to H.265/264 and well it’s slower than molasses in the winter.

Also I want a machine I can run lots of VM’s on and well i don’t really know what else yet as I haven’t quite figured that part out :rofl:

If all you are doing is vms and ideo encoding. The V2 socket 2011 chips are cheap as owt.

You could build a 1.8ghz 12 core single cpu beast with 64gb of ram for <$300.