Impact of adding 32Gb RAM to PO3-620

Enginayer

Hi Folks,

I'd like help understanding the RAM in the as-built Acer Orion Predator (PO3-620-EB13) I just bought (w/2x8Gb pre-installed), and then predict what will happen if I install 2x16 Gb Kingston DDR4 3200 MHz CL16-18-18 @ 1.35V "XMP Certified" (KF432C16BB1K/32). Notice that the datasheet has a single JEDEC default of "DDR-2400 CL17-17-17 @ 1.2V".  I've attached two images showing my current 2x8 GByte Max Bandwidth "DDR4-3200 (1600 MHz)" pre-installed.  The part number on the OEM RAM (ACR32D4U2S1ME-8) doesn't have much info online.   

I'm a victim of trying to match the installed/advertised "3200 MHz"; so I purchased 2 sticks of 16Gb @ 3200 MHz that are now hard and expensive to return. I understand (after purchasing the 3200 MHz) that 2666Mhz is the recommended RAM speed. My post is more about "How bad will it be if I do it anyway?".

Understanding

(aka N00b Questions)

• Q1. Given the "Memory" tab of CPU-Z shows "1463.2MHz", does that mean the mobo has chosen to use JEDEC #11? Is this expected? Should I not see 1600 MHz (ie JEDEC #14)? 
• Q2. Is there somewhere online I can look up the SPD Timings Tables, ideally based on part number? Does all RAM have (at least?) 4 permutations of timings that it will work at?

Predicting

I've reviewed several past threads on these boards. I want to summarize what I've learned.  If any of the following is not accurate, or current, please please please correct me.  Consider them assumptions I'd like validated or conversations starters.

• Q3. XMP is incompatible with the H470 chipset in my (all?) PO3-620 machines.  The outcome is that if you try to use XMP compatible RAM, you'll get some (unknowable?) lower JEDEC default speed. Is this all true?
• Q4. The BIOS is terrible/limited, so we can't manually control RAM timings.  The outcome is that the mobo might choose really low speeds and there is nothing I can do about it. Is this still current?
• Q5. Given the above, if I install the 2x16Gb, which scenario is likely to be the outcome?

A0 - 48Gb @ < 1200 MHz - ie the documented 2400 MHz JEDEC isn't the worst case, DRAM frequency for all RAM drops to something terrible as the lowest common-denominator.
A1 - 48Gb @ 1200 MHz - ie the documented 2400 MHz JEDEC default kicks in on the new RAM, DRAM frequency for all RAM drops to 1200 MHz as the lowest common-denominator.
A2 - 48Gb @ > 1200 and < 1454 MHz - Some other (unknowable, but higher than 1200 MHz), RAM timing kicks in on the new RAM, DRAW frequency for all RAM drops to something like 1333 MHz.
A3 - 48Gb @ 1454 MHz - ie the new ram is undocumented but compatible with JEDEC #11 (1454 MHz), so no degradation of DRAM frequency and 48Gb is useable.
B1 - RAM timings are so different, my machine won't boot with both sets installed.
B2 - RAM timings are so different, my machine risks being damaged with both sets installed.

• Q6. - Will I even notice the difference between 1200 and 1454?

• Q7. Given the above, if I installed 2x16Gb and removed the 2x8Gb, which scenario is likely to be the outcome?

C1 - 32Gb @ 1200 MHz - ie the documented 2400 MHz JEDEC default kicks in on the new RAM.
C2 - 32Gb @ ? MHz - there is guaranteed to be some higher undocumented JEDEC default on the new RAM. Can't know until you try.

I have no other mods to this machine.

Thanks for reading and any insights you might be able to teach me and future readers.

messer89

always when you install an xmp ram on non xmp mobo the ram will run on it's lowest base speed, no matter on what other ram sticks you have

Enginayer

So - how do I know the "lowest base speed" of the RAM I linked above? Will it still do that, on this mobo, even if other RAM in the mobo is at its lowest? 

I'm trying to figure out if I should go through the cost and time of returning it and getting non-XMP.  Any details beyond my post would be helpful and appreciated.

messer89

Enginayer said:

So - how do I know the "lowest base speed" of the RAM I linked above? Will it still do that, on this mobo, even if other RAM in the mobo is at its lowest? 

You have written in that PDF you linked that the lowest base speed of your RAM is 2400Mhz.

Enginayer said:

I'm trying to figure out if I should go through the cost and time of returning it and getting non-XMP.  Any details beyond my post would be helpful and appreciated.

If you want faster memory than 2400Mhz then yes, go for it.

Enginayer said:

Will it still do that, on this mobo, even if other RAM in the mobo is at its lowest? 

Yes, It will.

Also remmember that if you have for example 10th gen F-series intel processor it doesn't need RAM faster than 2933Mhz.

And you wrote something about CPU-Z. You need to know it often shows incorrect values. Check your ram speeds in Crucial system scanner.

Enginayer

I returned the ram linked above, thanks so much for your help.  

Scanners show I have:

* The crucible system scanner says the speed is 3200.
* UserBenchmark.com's scanner says 3200 MHz clocked @ 2933 MHz. 
* Predator Sense says the speed is 3200 MHz.
* CPU-Z shows a DRAM frequency of 1463.2MHz. (No idea what this is).

Which RAM do I buy then? Given...

* I want to keep the 16 Gb I have now.
* I don't want to slow down my machine.
* I want either 2x8Gb or 2x16Gb, depending on price.
* If it says XMP, I'm ignoring it.

Do any of these make sense?

PATRIOT
Patriot Signature Premium DDR4 32GB (2x16GB) 2666MHz (PC4-21300) UDIMM kit with Heatshield ($144 CAD on Amazon)
PSP432G2666KH1
Note: Tom's Hardware Guide confirmed that this part number is "Standard" RAM. They explicitly state that it's not XMP. 
CRUCIALCrucial RAM 16GB Kit (2x8GB) DDR4 3200MHz CL22 (or 2933MHz or 2666MHz) Desktop Memory ($133 CAD on Amazon)
CT2K8G4DFRA32A

KINGSTON
Kingston 16GB 2933MHz DDR4 Non-ECC CL21 DIMM 2Rx8 ($122 CAD on Amazon)
KVR29N21D8/16 

StevenGen

Enginayer said:

I returned the ram linked above, thanks so much for your help.  

Scanners show I have:

* The crucible system scanner says the speed is 3200.
* UserBenchmark.com's scanner says 3200 MHz clocked @ 2933 MHz. 
* Predator Sense says the speed is 3200 MHz.
* CPU-Z shows a DRAM frequency of 1463.2MHz. (No idea what this is).

Which RAM do I buy then? Given...

* I want to keep the 16 Gb I have now.
* I don't want to slow down my machine.
* I want either 2x8Gb or 2x16Gb, depending on price.
* If it says XMP, I'm ignoring it.

Do any of these make sense?

PATRIOT

Patriot Signature Premium DDR4 32GB (2x16GB) 2666MHz (PC4-21300) UDIMM kit with Heatshield ($144 CAD on Amazon)
PSP432G2666KH1

Note: Tom's Hardware Guide confirmed that this part number is "Standard" RAM. They explicitly state that it's not XMP. 

CRUCIAL

Crucial RAM 16GB Kit (2x8GB) DDR4 3200MHz CL22 (or 2933MHz or 2666MHz) Desktop Memory ($133 CAD on Amazon)
CT2K8G4DFRA32A

KINGSTON
Kingston 16GB 2933MHz DDR4 Non-ECC CL21 DIMM 2Rx8 ($122 CAD on Amazon)
KVR29N21D8/16 

If your PO3-620 has the i7-10700 then this CPU's - Memory Specifications > Memory Types runs at max DDR4-2933 at max capacity of 128 GB. From your CPUz “Memory” caption the 2x 8GB DDR4-3200MHz memory speeds are both running at DRAM Frequency of 1463.5 x 2 = 2927MHz which and if you look at your Task Manager > Performance > Memory > Speed you will get that sort of RAM speed of around 2927MHz. As its been pointed out to you, if you fit/run the DDR4-3200MHz (must be a none overclocked RAM) then the speeds will always be to what the CPU’s memory specs maxes out at which is 2933MHz like your CPUz “Memory >DRAM Frequency figures” are showing, also and putting DDR4-2666MHz will be a much slower RAM and will run at 2666MHz.

billsey

Yes, I would select the 2933 ram from your options, since it saves you some money and provides the same performance. I believe the only reason Acer installed 3200 was because they had a better price or better availability with that.