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I'm picking a SDRAM IC for a custom embedded board and was surprised by the low prices. Was expecting orders of magnitude similar to PC ram of the same capacity.

For example H5TC8G63AMR-PBA chip costs almost 4 times less than this Corsair Vengeance 8GB (1x8GB) DDR3 1600 MHz (PC3 12800).

Digging into the datasheet [page 4] for the RAM on chip it states that it its configuration is 512M x 16 and the speed isn't clear from the name.

  • Is the speed the main reason for the difference?
  • Are there other factors (like a need for a PCB) that multiply the price?
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    \$\begingroup\$ Are you comparing one chip with a DDR stick that contains eight of the same chip? \$\endgroup\$ – pjc50 Nov 23 '16 at 16:47
  • \$\begingroup\$ Have you calculated how much of the chips you need for the same capacity? Plus the PCB? Plus manufacturers need to make money? \$\endgroup\$ – PlasmaHH Nov 23 '16 at 16:48
  • \$\begingroup\$ @pjc50 The reference for the chip states DDR3 8Gbit 512MBx16 0-70C. From that I've assumed the 8Gbit is the capacity of the chip. \$\endgroup\$ – TheMeaningfulEngineer Nov 23 '16 at 16:51
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    \$\begingroup\$ @Alan Correct, 8 Gbit. Which means you need 8 of them to get 8 GBytes of memory. \$\endgroup\$ – Andrew Nov 23 '16 at 16:52
  • \$\begingroup\$ @Andrew So it should be 512Mbx16 instead of 512MBx16? \$\endgroup\$ – TheMeaningfulEngineer Nov 23 '16 at 16:54
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To put the comments into the form of an answer so that the question can get closed...

The SDRAM part linked to is a 512Mx16 device, 512M addresses, 16 bits wide giving a total of 8Gbits.

The DIMM linked has a capacity of 8GBytes, 8 times the capacity of the individual memory chip.

The DIMM also lists its speed as PC1600 with timings of 10-10-10. For the memory chip the -PBA at the end indicates that it is PC1600 with timings of 11-11-11 (the PB) in a x16 configuration (the A).

So while the DIMM is 4 times the price you are getting 8 times the memory that can run 10% faster.

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    \$\begingroup\$ And the length-matched impedance-controlled properly-terminated board for free ;) \$\endgroup\$ – Sam Nov 23 '16 at 22:28

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