Question I don't understand RAM very well; please advice on this simple question.

doumqc

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I currently have one stick of 16GB DDR4 ram running at 1665.7 MHz according to CPU-Z. It's a generic stick not recognized by CPU-Z, but if i remember correctly the brand is Team from the label.
I was gifted GeIL EVO X II AMD Edition 32GB (2 x 16GB) 288-Pin DDR4 SDRAM DDR4 3000 (PC4 24000) Desktop Memory Model GAEXSY432GB3000C16ADC.
My initial thought was to upgrade to 48 GB, but I seem to recall that 3 sticks of RAM is not optimal, something about dual channel...

Can someone please confirm that I would be better off with the 2x16GB only versus a 2x16GB + 16GB setup in terms of performance? Asking for peace of mind.

Thank you!
 
How the RAM acts is determined by 3 things: Your motherboard, your CPU, and the RAM modules. No one here can help you without more information. You need to provide the full specifications of your machine inclusding the PSU model, make, and age.
 

doumqc

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How the RAM acts is determined by 3 things: Your motherboard, your CPU, and the RAM modules. No one here can help you without more information. You need to provide the full specifications of your machine inclusding the PSU model, make, and age.
I really do apologize, as I thought the answer was always the same regardless of the rest (Example: 3 sticks is never optimal). I know you guys must be continuously annoyed by questions asked without the proper information provided. Here, and I'll check my PSU in a few minutes:

 

doumqc

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https://www.intel.com/content/www/us/en/support/articles/000005657/boards-and-kits.html
Looks like whatever you do, if it even works, 3rd stick will always run singlechannel mode.
I don't know how AMD handles it because I have never run 1 stick/single channel. Outside of checking if a RAM stick is broken.
What I don't understand is if the two new sticks can run dual channel while the third runs single, or if the "lone" stick will make everything else run single channel also.
I suppose that 32 GB dual channel is "better" than 48GB running single channel, but I have no clue to be honest... :(
 

GaryM

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For most usage cases, 32GB should be plenty of memory, so unless you have really unusual needs, you can keep the unmatched DIMM as a spare. The Team memory may also be slower than the Geil memory, and that would be the biggest downside to using it, because all memory has to run at the speed of the slowest stick.

Regarding your comment that CPU-Z doesn't recognize the Team memory, you may be missing something... On the "SPD" tab, you may be seeing all blanks in the info windows, but that may be because slot #1 is empty. Adjust the drop-down control to show slot #2, slot #3, or slot #4 until CPU-Z shows you the memory specs. I'm guessing this is why you're not seeing the expected information. CPU-Z should also show you the maximum rated speed for the Team memory, and then you'll know if using it would impede the Geil memory, which is likely faster. And as was already mentioned, an unmatched DIMM always runs in single-channel mode, slowing down some memory transfers. So combining all the DIMMs probably won't give you the best performance. Someone gave you a pretty cool gift that will likely be a nice boost due to reduced memory paging.
 

doumqc

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For most usage cases, 32GB should be plenty of memory, so unless you have really unusual needs, you can keep the unmatched DIMM as a spare. The Team memory may also be slower than the Geil memory, and that would be the biggest downside to using it, because all memory has to run at the speed of the slowest stick.

Regarding your comment that CPU-Z doesn't recognize the Team memory, you may be missing something... On the "SPD" tab, you may be seeing all blanks in the info windows, but that may be because slot #1 is empty. Adjust the drop-down control to show slot #2, slot #3, or slot #4 until CPU-Z shows you the memory specs. I'm guessing this is why you're not seeing the expected information. CPU-Z should also show you the maximum rated speed for the Team memory, and then you'll know if using it would impede the Geil memory, which is likely faster. And as was already mentioned, an unmatched DIMM always runs in single-channel mode, slowing down some memory transfers. So combining all the DIMMs probably won't give you the best performance. Someone gave you a pretty cool gift that will likely be a nice boost due to reduced memory paging.
Thank you very much. CPU-Z seems to actually recognize the TeamGroup manufacturer, it was Speccy that was giving me the information "16.0GB Single-Channel Unknown @ 1665MHz (18-22-22-42)" unlike my other PCs from which Speccy was able to identify the RAM maker and model.

RAM is complicated. The current 16GB has a listed potential speed of 3333Mhz, but is running at 1666 MHz. This is probably a question that is asked very very often and from what I've read, this is normal as DDR means Dual Data Rate so there's actually a x2 multiplier. Not really that important for me now, as I'm about to remove that stick for the other 2.
 

Endre

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I currently have one stick of 16GB DDR4 ram running at 1665.7 MHz according to CPU-Z. It's a generic stick not recognized by CPU-Z, but if i remember correctly the brand is Team from the label.
I was gifted GeIL EVO X II AMD Edition 32GB (2 x 16GB) 288-Pin DDR4 SDRAM DDR4 3000 (PC4 24000) Desktop Memory Model GAEXSY432GB3000C16ADC.
My initial thought was to upgrade to 48 GB, but I seem to recall that 3 sticks of RAM is not optimal, something about dual channel...

Can someone please confirm that I would be better off with the 2x16GB only versus a 2x16GB + 16GB setup in terms of performance? Asking for peace of mind.

Thank you!
Hello!

Yes, you are correct.
2x16GB + 16GB is a bad idea.
(All modules will run at the speed of the slowest one).

First of all, you should never mix RAM modules, especially when they are not the same model!

I hope this helps...
 

GaryM

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Not really that important for me now, as I'm about to remove that stick for the other 2.
Since this is your first use of 2 DIMMs, be sure to consult your motherboard manual so you're putting them in the optimal slots. On mine, the correct slots were #2 and #4, so it may not be obvious without instructions.
 

geofelt

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The first rule for ram is to get enough.
If you have more than you need, windows just keeps extra code in ram in anticipation of possible quick reuse.
Today, with 16gb of ram, look at task manager/memory tab/hard fault page rate.
If you see zero, windows never ran out of available ram.
If you see 1 or more, you do not have enough ram.

Since you were given a 2 x 16gb kit of 3000 speed ram, I would install that, even if it might be more than you need.
Because of dual channel operation, the effective ram speed will be 3000.
Your original ram is probably marked as 3200 speed but that is only in dual channel mode.
Effectively, you are now operating at 1666.

What is your processor and motherboard?
If it is Intel, real app performance(vs. synthetic ram benchmarks) will not be much impacted by speed.
If you have ryzen, speed and compatibility is very important.

If you want to try adding the old 16gb it may work. The extra stick will operate in single channel mode while the 32gb will be in dual channel mode.
That is called flex mode.
Adding the 16gb stick may not work at all since ram must be matched.
It all must run at the same speed, voltage, and timings.
Internal differences may make the extra stick incompatible.
 

doumqc

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The first rule for ram is to get enough.
If you have more than you need, windows just keeps extra code in ram in anticipation of possible quick reuse.
Today, with 16gb of ram, look at task manager/memory tab/hard fault page rate.
If you see zero, windows never ran out of available ram.
If you see 1 or more, you do not have enough ram.

Since you were given a 2 x 16gb kit of 3000 speed ram, I would install that, even if it might be more than you need.
Because of dual channel operation, the effective ram speed will be 3000.
Your original ram is probably marked as 3200 speed but that is only in dual channel mode.
Effectively, you are now operating at 1666.

What is your processor and motherboard?
If it is Intel, real app performance(vs. synthetic ram benchmarks) will not be much impacted by speed.
If you have ryzen, speed and compatibility is very important.

If you want to try adding the old 16gb it may work. The extra stick will operate in single channel mode while the 32gb will be in dual channel mode.
That is called flex mode.
Adding the 16gb stick may not work at all since ram must be matched.
It all must run at the same speed, voltage, and timings.
Internal differences may make the extra stick incompatible.
Wow very interesting, I did not know about flex mode! 32 GB of RAM will most likely be enough for my gaming needs, but I'm still curious about all this. I do have a Ryzen. Can you see the following picture? Would you say the new GelL RAM is a good fit for this system? Thanks so much for these information.

 

geofelt

Titan
Ryzen is very much tied to ram, both for performance and compatibility.
Flex mode may not apply.
I would not even try to add it.
Since you have the 32gb in hand, try it.
Not all DDR4 ram will be compatible.
If you have difficulties, check to see if your motherboard bios has an update that addresses ram issues.
 

doumqc

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Ryzen is very much tied to ram, both for performance and compatibility.
Flex mode may not apply.
I would not even try to add it.
Since you have the 32gb in hand, try it.
Not all DDR4 ram will be compatible.
If you have difficulties, check to see if your motherboard bios has an update that addresses ram issues.
The BIOS has been flashed and the new RAM has Ryzen logos all over it. I guess I'm in luck!
 

doumqc

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Ryzen is very much tied to ram, both for performance and compatibility.
Flex mode may not apply.
I would not even try to add it.
Since you have the 32gb in hand, try it.
Not all DDR4 ram will be compatible.
If you have difficulties, check to see if your motherboard bios has an update that addresses ram issues.
Well, believe or not, I managed to screw this up. First try, no bios, no keyboard, nothing, but the fans are going. After long hours of troubleshooting, rolling back to the original stick, trying one at the time in different slots, etc., it appears that one of the new Gell stick is faulty. Did I damage it during installation? I don't know, perhaps. Anyhow, I'm lucky that the one I already had, listed at 3200Mhz CL18 can run in dual channel perfectly with the XMP profile of the new ones (listed at 3000Mhz CL16). They are not the same, but they run in dual channel at 2993MHz 16-18-18-18-36, which is exactly what the new pair was going to be running. Performs well in various benchmarks, so all is well.
However, it's very frustrating not the have the identical pair working together, even if that doesn't seem to be affecting performance.

Thanks for all the advices.
 

GaryM

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I'm lucky that the one I already had, listed at 3200Mhz CL18 can run in dual channel perfectly with the XMP profile of the new ones (listed at 3000Mhz CL16). They are not the same, but they run in dual channel at 2993MHz 16-18-18-18-36, which is exactly what the new pair was going to be running. Performs well in various benchmarks, so all is well.
LOL!!!
At 11:11 AM, you wrote "I don't understand RAM very well."
And then by 9:49 PM, you're talking like a damn PRO! You're a quick study(y)
 

doumqc

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LOL!!!
At 11:11 AM, you wrote "I don't understand RAM very well."
And then by 9:49 PM, you're talking like a damn PRO! You're a quick study(y)
HAHA! Funny observation. I should have mentionned that I'm definitly not a complete noob when it comes to hardware. I knew RAM could run at a lower frequency than the listed one, and also higher with overclocking and XMP profiles. However, those numbers : 16-18-18-18-36 are still pretty mysterious to me. I believe it's about the latency and that there is a link with the CL16 our CL18 mentionned on the sticks. I THINK lower is better, but I'm not sure about that. What I didn't know is that a stick that is marked as CL18 can apparently run at 16 latency, so I guess you can "overclock" the latency too. There are many profiles to try in "Memory Try It!" of the bios, but I have no clue. 3066 at 16-18-18-38 or 3066 at 18-22-22-48, I got no damn clue!
 

GaryM

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@doumqc, now that you have your memory running stable at about 3000 MHz, there's one more thing you might want to check and possibly adjust in the BIOS. With your DDR memory, the actual clock frequency (MCLK) is really just 1500 MHz, and in most cases your memory transfers will be optimized if you set the infinity fabric clock (FCLK) to that same frequency for well-synchronized data transfers. Corsair explains it far better than I ever could...
https://www.corsair.com/corsairmedia/sys_master/productcontent/Ryzen3000_MemoryOverclockingGuide.pdf

I don't know if this is ever done automatically, but I know when I set up my BIOS to use the XMP/DOCP profile, I had to make a separate adjustment to the FCLK.
 

doumqc

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Hardware manufacturers: Let's have an option called XMP that automatically overclocks RAM to optimized settings.
Manager: "Too easy, make sure there is another hidden setting somehwere that they'll have to adjust manually for optimal performance.

Just kidding, thanks for that link, it's a great guide!
 
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