8x8GB of DDR3, go with regular DIMMS or find UDIMMs?

[CerealExperimentsLain]

If you look at my signature, you see I have two Asus X79 systems doing UnRAID.  You'll also see they're not really maxed out on RAM.  Do have 8x8GB of DDR3 but it gives me problems, while all mostly of nearly the same type, some have slightly different PCBs and two of the sticks will not play nice with the other 6 and cause hangups, refuse to boot, crash, even at reduced clock speed.  Any combination of the 8 sticks in in 4 stick kits works flawlessly, 6 of them also work fine in an 8 slot system, you add the two other to the other 6 and you have issues.

Before anyone asks, no, this is an official X79 board, it does not support Registered/Buffered ECC, only Unregistered/Unbuffered ECC. (And I think the ECC function doesn't even work when using UDIMMs).  I've tried it with RDIMMs.  I've looked for BIOS mods.  Nothing. RDIMMs will not work, only DIMMs or UDIMMs.

 

So there is the queston, would it be cheaper to hunt down an 8x8GB DIMM or UDIMM kit?  UDIMMs are not nearly as common on the used market as RDIMMs.  ...Or as cheap, since the used market is flooded with RDIMMs.

[NelizMastr]

Forget about ECC unless you're swapping the X79 boards for actual server boards with a C-series chipset. Intel locked ECC away from X79 so UDIMM/RDIMM is irrelevant.

You'll be limited to 8GB DIMMs without RDIMM support, so there's no fix for that, sadly.

[CerealExperimentsLain]

1 minute ago, NelizMastr said:

Forget about ECC unless you're swapping the X79 boards for actual server boards with a C-series chipset. Intel locked ECC away from X79 so UDIMM/RDIMM is irrelevant.

You'll be limited to 8GB DIMMs without RDIMM support, so there's no fix for that, sadly.

Right... The question was about which on the used market is likely to be cheaper, DIMMs or UDIMMs, as the obviously very cheap RDIMMs are off the table.

[Eighjan]

7 minutes ago, CerealExperimentsLain said:

If you look at my signature, you see I have two Asus X79 systems doing UnRAID.  You'll also see they're not really maxed out on RAM.  Do have 8x8GB of DDR3 but it gives me problems, while all mostly of nearly the same type, some have slightly different PCBs and two of the sticks will not play nice with the other 6 and cause hangups, refuse to boot, crash, even at reduced clock speed.  Any combination of the 8 sticks in in 4 stick kits works flawlessly, 6 of them also work fine in an 8 slot system, you add the two other to the other 6 and you have issues.

Before anyone asks, no, this is an official X79 board, it does not support Registered/Buffered ECC, only Unregistered/Unbuffered ECC. (And I think the ECC function doesn't even work when using UDIMMs).  I've tried it with RDIMMs.  I've looked for BIOS mods.  Nothing. RDIMMs will not work, only DIMMs or UDIMMs.

 

So there is the queston, would it be cheaper to hunt down an 8x8GB DIMM or UDIMM kit?  UDIMMs are not nearly as common on the used market as RDIMMs.  ...Or as cheap, since the used market is flooded with RDIMMs.

Eight 8GB sticks will always work best as a matched set... even eight of the same single sticks could cause issues.

 

A totally matched set of eight 8GB modules may be 'fun' to source; new may well be more efficient.

[CerealExperimentsLain]

1 minute ago, Eighjan said:

Eight 8GB sticks will always work best as a matched set... even eight of the same single sticks could cause issues.

Yup and consumer 8 stick kits are not common.  It's one reason I've been eyeballing UDIMMs, since they're used enterprise products, they usually at least are selling buckets of identical UDIMMs even if not nearly as cheap as RDIMMs.

[Eighjan]

1 minute ago, CerealExperimentsLain said:

Yup and consumer 8 stick kits are not common.  It's one reason I've been eyeballing UDIMMs, since they're used enterprise products, they usually at least are selling buckets of identical UDIMMs even if not nearly as cheap as RDIMMs.

R/U-DIMMs are probably easier to find 'cos they're harder to shift. 

[NelizMastr]

4 minutes ago, CerealExperimentsLain said:

Right... The question was about which on the used market is likely to be cheaper, DIMMs or UDIMMs, as the obviously very cheap RDIMMs are off the table.

ECC UDIMMs are more expensive than regular non-ECC UDIMMs. Non-ECC UDIMMs were only used in low end servers. I've never seen them for very cheap.

[Eighjan]

A quick look on PC Part Picker show these as options; may help your search:

https://uk.pcpartpicker.com/products/memory/#Z=65536008&U=3&sort=fwl&page=1