Does the i9-9980XE have a hard limit of 128GB RAM?

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Thunderdolt

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I'm wondering if the 128GB limit is a hard controller limit, or if it is just a soft limit based on the maximum single DIMM capacity that was available at the time. Now that higher capacity modules are out, is it possible to run 256GB with this CPU?
 
ark.intel.com says " Max Memory Size (dependent on memory type) 128 GB" when looking up the i9-9980XE.
 
Doubtful that the non-registered double-capacity modules that made it onto the market recently will work, as they're technically doubling the ranks per channel and there is a hard limit on the number of ranks in a system, dependent on the IMC design. If ECC were supported this would be a no-brainer as there are plenty of 32GB registered DDR4 modules for sale.
 
Thunderdolt said:
I'm wondering if the 128GB limit is a hard controller limit, or if it is just a soft limit based on the maximum single DIMM capacity that was available at the time. Now that higher capacity modules are out, is it possible to run 256GB with this CPU?
Click to expand...

If you need 256GB, I think you need to step up to a Xeon W-2195 or AMD's Threadripper 2990WX.
 
techguymaxc said:
Doubtful that the non-registered double-capacity modules that made it onto the market recently will work, as they're technically doubling the ranks per channel and there is a hard limit on the number of ranks in a system, dependent on the IMC design. If ECC were supported this would be a no-brainer as there are plenty of 32GB registered DDR4 modules for sale.
Click to expand...
I'm glad ECC isn't supported on this chip - I may be crazy enough to buy it if so
 
In the past, at least DDR3, most CPUs were capable of addressing more memory than they were rated for. The i7 920 was rated for 24gb RAM and people had success running 48gb. I would think this would be the case here too, but there's really only one way to find out.
 
Armenius said:
It's a limit of the IMC.
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No it's not. It's a hard limit on unregistered DIMMs.

You can install registered DIMMs on some Gigabyte motherboards with SPECIFIC BIOS revs to unlock support up to 64GB per-DIMM, but you get no ECC support.

https://forums.tomshardware.com/threads/x299-512-ecc-r-dimm.3268738/

And YES, 64GB is the max size of DDR4 DIMMs.

I would just treat the 128GB limit as your actual limit, as it seems they stopped supporting the hack, and even removed the product spec page announcing it;'s official support.
 
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chithanh said:
I think ECC has a role everywhere you cannot afford data corruption.
With servers it is of course crucial as data is kept in cache for long periods of time.
Click to expand...

Well yes but you really have to create a scenario at least as a home user to need ECC besides a home server.
 
defaultluser said:
You can install registered DIMMs on some Gigabyte motherboards with SPECIFIC BIOS revs to unlock support up to 64GB per-DIMM, but you get no ECC support.

https://forums.tomshardware.com/threads/x299-512-ecc-r-dimm.3268738/

And YES, 64GB is the max size of DDR4 DIMMs.
Click to expand...

Despite using this BIOS, however, I would still be locked down by the IMC's limit, right?

tangoseal said:
Well yes but you really have to create a scenario at least as a home user to need ECC besides a home server.
Click to expand...

I am the unicorn home user, which is why I had to start the thread to ask. As a consultant, I run weapons-grade hardware at home. As the combined CEO, CFO, and CIO of my own consulting gig, I have trouble approving lower-performing Xeon-branded setups when the prices end up being 5x what a "gaming" rig would cost. My next round of hardware spends rest on whether I can get 256GB into a single CPU non-Xeon rig.
 
Thunderdolt said:
Despite using this BIOS, however, I would still be locked down by the IMC's limit, right?



I am the unicorn home user, which is why I had to start the thread to ask. As a consultant, I run weapons-grade hardware at home. As the combined CEO, CFO, and CIO of my own consulting gig, I have trouble approving lower-performing Xeon-branded setups when the prices end up being 5x what a "gaming" rig would cost. My next round of hardware spends rest on whether I can get 256GB into a single CPU non-Xeon rig.
Click to expand...

I run a Xeon with ECC 24/7 Its my NAS among other things it does.
 
defaultluser said:
No it's not. It's a hard limit on unregistered DIMMs.

You can install registered DIMMs on some Gigabyte motherboards with SPECIFIC BIOS revs to unlock support up to 64GB per-DIMM, but you get no ECC support.

https://forums.tomshardware.com/threads/x299-512-ecc-r-dimm.3268738/

And YES, 64GB is the max size of DDR4 DIMMs.

I would just treat the 128GB limit as your actual limit, as it seems they stopped supporting the hack, and even removed the product spec page announcing it;'s official support.
Click to expand...

Also, if you need that much RAM chances are stability is important to you. You can't guarantee that in an unsupported configuration like that.
 
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