How to determine density of a memory module?

[dfk]

for example if both 4GB dimms below are single sided (physical chips only on one side of PCB).

2Rx8 = 16 chips = 256*16 = 4096 (lower density?)
1Rx8 = 8 chips = 512*8 = 4096 (this should be high density)

the terms high and low seems subjective, so how can one determine if a specific 2Rx8 or 1Rx8 is supported by a motherboard (assuming QVL lists are no longer updated since).

how to specifically look for low density modules to ensure compatibility?

 

[Pinhedd]

for example if both 4GB dimms below are single sided (physical chips only on one side of PCB).

2Rx8 = 16 chips = 256*16 = 4096 (lower density?)
1Rx8 = 8 chips = 512*8 = 4096 (this should be high density)

the terms high and low seems subjective, so how can one determine if a specific 2Rx8 or 1Rx8 is supported by a motherboard (assuming QVL lists are no longer updated since).

how to specifically look for low density modules to ensure compatibility?

4GiB per DIMM = 32Gib per DIMM

32Gib / 2 ranks = 16Gib per rank

16Gib per rank / 8 chips per rank = 2Gib per chip

alternatively,

32Gib / 1 rank = 32Gib per rank

32Gib per rank / 8 chips per rank = 4Gib per chip

4Gib DDR3 chips are considered to be "high density" for the purposes of motherboard compatibility

 

[dfk]

thanks Pinhedd, but u lost me there sorry.

i think what i wrote earlier was mistaken. this is example taken from kingston:

HyperX HX316C10FB/8 is a 1G x 64-bit (8GB) DDR3-1600 CL10 SDRAM (Synchronous DRAM) 2Rx8 memory module, based on sixteen 512M x 8-bit DDR3 FBGA components.

HX316C10FB/8 8GB HyperX Fury:
1G x 64-bit (8GB) 2Rx8 / sixteen 512M x 8-bit FBGA

HX316C10F/4 4GB HyperX Fury:
512M x 64-bit (4GB) 1Rx8 / eight 512M x 8-bit FBGA

KVR 4GB:
512M x 64-bit (4GB) 2Rx8 / sixteen 256M x 8-bit FBGA

i understand that the 8GB Fury is dual ranked, double sided, as with the KVR, and the 4GB Fury is single ranked, single sided.

how does one determine which is high/low density?

 

[Pinhedd]

thanks Pinhedd, but u lost me there sorry.

i think what i wrote earlier was mistaken. this is example taken from kingston:

HyperX HX316C10FB/8 is a 1G x 64-bit (8GB) DDR3-1600 CL10 SDRAM (Synchronous DRAM) 2Rx8 memory module, based on sixteen 512M x 8-bit DDR3 FBGA components.

HX316C10FB/8 8GB HyperX Fury:
1G x 64-bit (8GB) 2Rx8 / sixteen 512M x 8-bit FBGA

HX316C10F/4 4GB HyperX Fury:
512M x 64-bit (4GB) 1Rx8 / eight 512M x 8-bit FBGA

KVR 4GB:
512M x 64-bit (4GB) 2Rx8 / sixteen 256M x 8-bit FBGA

i understand that the 8GB Fury is dual ranked, double sided, as with the KVR, and the 4GB Fury is single ranked, single sided.

how does one determine which is high/low density?

512M = 4Gib = high density

256M = 2Gib = not high density

 

[dfk]

Thanks! What does 1G x 64-bit stand for though? is it memory bus width? why does some use 1G and lower capacity ones use 512MB.