256 GB of RAM. ECC or not?

[Heavybell]

Please don't ask why, but I'm considering upgrading my home 'workstation' / gaming PC to 256 GB of RAM.

 

It's a Threadripper 3960x on an ASUS ROG Strix TRX40-E Gaming motherboard, and I'm currently considering these options:

 

G.SKILL RIPJAWS V 256GB (8X32GB) PC4-28800 (3600MHZ) DDR4

KINGSTON SERVER PREMIER KSM32ED8/32ME 32GB 3200MHZ ECC UNBUFFERED DDR4

 

Of course... this is a lot of money, so I would like a 2nd opinion. Not on the amount of RAM, but if ECC would be worth it at this scale? Would it be worth trying to run the ECC RAM at 3600 MHz? Does being ECC somehow sidestep the potential for some sticks to not work with eachother, or would I be better off going non-ECC just so I can get a multi-stick kit that presumably works together?

[Guest]

I highly doubt you'll be running 3600mt/s with 256gb installed. 

[Oshino Shinobu]

If you're spending that much anyway, I'd go for ECC. 

 

I wouldn't try to push the RAM any higher than its specs state. ECC is designed for stability, defeats the purpose to try to push it beyond its specs and introduce potential instability. 

 

As far as I know, ECC doesn't do anything to help with compatibility with other sticks. Though while it's anecdotal, I have 128GB of RDIMM ECC in my own server, all 8 sticks purchased individually (though they are the exact same model) and they work perfectly together. It's fairly rare to come across sticks of the same model that won't work together now days. 

[Heavybell]

1 minute ago, Oshino Shinobu said:

If you're spending that much anyway, I'd go for ECC. 

 

I wouldn't try to push the RAM any higher than its specs state. ECC is designed for stability, defeats the purpose to try to push it beyond its specs and introduce potential instability. 

 

As far as I know, ECC doesn't do anything to help with compatibility with other sticks. Though while it's anecdotal, I have 128GB of RDIMM ECC in my own server, all 8 sticks purchased individually (though they are the exact same model) and they work perfectly together.

These are all good points.

[Guest]

4 minutes ago, Oshino Shinobu said:

It's fairly rare to come across sticks of the same model that won't work together now days. 

Bite the tongue and knock on wood! HAHA!!

Plenty of mixed match thread issues in this forum. 

 

256GB, expectations on frequency, 2667mt/s. ECC especially. 

[Quackers101]

ECC would be slower, but less errors? but with DDR5 it's built into the system?

depends on what you need. think most if not all servers use ECC.

not sure if it makes a difference for you, but I guess it also depends on what you are going to use it for?

Also if you think the cost is worth it.

[Heavybell]

8 minutes ago, ShrimpBrime said:

Bite the tongue and knock on wood! HAHA!!

Plenty of mixed match thread issues in this forum. 

 

256GB, expectations on frequency, 2667mt/s. ECC especially. 

I can definitely confirm that as recently as a couple years ago I got a bunch of individual Kingston RAM sticks of the exact same type and they did not all work in a 1st gen Threadripper build.

 

So you're saying even if I got 3200mt/s rated ECC RAM, at that scale it'd need to be clocked down to 2667 to work?

[Guest]

Just now, Heavybell said:

So you're saying even if I got 3200mt/s rated ECC RAM, at that scale it'd need to be clocked down to 2667 to work?

Yes, most definitely. 

ECC is designed for redundancy, not performance. 

[Heavybell]

10 minutes ago, ShrimpBrime said:

Yes, most definitely. 

ECC is designed for redundancy, not performance. 

I've been doing a little more looking around and I found this post claiming that populating all 8 RAM slots in TR gen 3 limits the officially supported frequency to 2666. I wonder if that might be why I'm having issues with my current setup. It has 8 sticks of non-ECC RAM running at 3600, and it's mostly okay... until weird issues occur.

[Guest]

3 minutes ago, Heavybell said:

I've been doing a little more looking around and I found this post claiming that populating all 8 RAM slots in TR gen 3 limits the officially supported frequency to 2666. I wonder if that might be why I'm having issues with my current setup. It has 8 sticks of non-ECC RAM running at 3600, and it's mostly okay... until weird issues occur.

CPU memory controller is only good for 3200mt/s. (3rd gen)

You can keep XMP enabled, manually reduce to 3200 and do some testing (normal use probably you get strange issues right?)

Also in the timings menu, you can disable "power down mode" which will prevent the memory from throttling while idle.

Edited October 21, 2021 by ShrimpBrime
inserted comment for clarity.

[Heavybell]

3 minutes ago, ShrimpBrime said:

CPU memory controller is only good for 3200mt/s. (3rd gen)

You can keep XMP enabled, manually reduce to 3200 and do some testing (normal use probably you get strange issues right?)

Also in the timings menu, you can disable "power down mode" which will prevent the memory from throttling while idle.

Yeah, I've already learned about power down mode, pretty sure that's off.

 

I'll try going back to 3200mt/s again, see if that helps.

 

As for the upgrade, perhaps 4x MICRON MTA18ASF4G72AZ-3G2B1 32GB (1X32GB) 3200MHZ ECC UDIMM DDR4 would make more sense? 'Only' 128 GB but would having less slots populated help hit 3200 safely?

[Guest]

18 minutes ago, Heavybell said:

 

 

As for the upgrade, perhaps 4x MICRON MTA18ASF4G72AZ-3G2B1 32GB (1X32GB) 3200MHZ ECC UDIMM DDR4 would make more sense? 'Only' 128 GB but would having less slots populated help hit 3200 safely?

The wording, safely..... 

 

128gb less slots populated will increase the chances, I promise nothing.

ECC typically runs 2667mt/s or slower. 

 

Let me try and find this one thread for you to read....

 

 

[Guest]

Found it. 

Notice the amount installed and so forth.

 

 

[Heavybell]

27 minutes ago, ShrimpBrime said:

Found it. 

Notice the amount installed and so forth.

 

 

What a frustrating read. What do the Micron datasheets list 3200mt/s if they cannot run at that speed?

[Guest]

24 minutes ago, Heavybell said:

What a frustrating read. What do the Micron datasheets list 3200mt/s if they cannot run at that speed?

Test a single stick is single channel, it'll probably run it's rated speed.....

[lacek]

On 10/21/2021 at 2:28 AM, Quackers101 said:

ECC would be slower, but less errors? but with DDR5 it's built into the system?

depends on what you need. think most if not all servers use ECC.

ECC in an umrella term for many specific terms, ECC in DDR5 is not "the ECC" one thinks of .  Just read it here: