How does Unraid decide installable memory capacity

[ekeskin]

Hi,

Posted this also to reddit, i don't know where do you guys most active.

I'm fairly new to unraid, repurposed one of my old system as NAS/Media Box with Sonarr Radarr Plex Transmission etc.

Currently have a i7-870, GA-P55-USB3 v1(i suppose) and 2x2G Kingston rams.

I checked for P55-USB3s specs sheet and states as

Quote

 

4 x 1.5V DDR3 DIMM sockets supporting up to 16 GB of system memory (Note 1)

 

and from Intel ARK page for i7-870:

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Max Memory Size (dependent on memory type) : 16 GB

 

But unraid seems to insist on

Quote

installed 4 GB
max. installable capacity 32 GB

But also i read on internet that people with i5-850s used 32GB ram with that motherboards(GA-P55-USB3, no version information).

 

Could I trust unraid and go for 4x8 setup or should I be conservative and buy 4x4 for 16 GB total ? Are there are ground for unraids max installable capacity spec ?

[remotevisitor]

This information comes from the BIOS on the motherboard and there are several reasons to explain the discrepancy:

 

1. The documented spec is correct and the BIOS incorrectly reports the wrong size.
2. The documented spec is incorrect and the BIOS reports the correct size.
3. Unraid for some reason is misinterpreting the reported size.

 

Now I suspect that in this case it is probably option 2;   When the motherboard was first released the BIOS probably did only support 16G and matched the specification.   However (assuming this may be a version 1 of the motherboard) the F8 version of the BIOS suggests there was a change in the supported memory capacity if you look at the release history for the BIOS: https://www.gigabyte.com/Motherboard/GA-P55-USB3-rev-10#support-dl-bios.  This would then explain why the specification and reported size by the BIOS differ.

 

However it is impossible to be 100% certain until you try it.

[ekeskin]

Oh i didn't think about BIOS updates. That could make sense.