Question Getting a very fast RAM

mujmuj

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I have this (#1).

#1: DRAM, DDR3 2133, 32GB (2X16GB)
https://www.amazon.com/gp/product/B016ORTNI2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I have 2 of this, so I have total 64GB. But this is DDR3 2133. So it's old I think.

I run STATA, which loads all data to RAM. So RAM speed is important. So I want to upgrade.


Last week I bought next one (#2).

#2: SDRAM, DDR4 3600, PC4 28800, 288-Pin, 64GB (2X32GB)
https://www.newegg.com/corsair-64gb-288-pin-ddr4-sdram/p/N82E16820236602?Item=N82E16820236602

But later I learned that there are things with faster RAM speed (#3).

#3: SDRAM, DDR4 5000, PC4-50000, 288-Pin, 16GB (2X8GB)
https://www.newegg.com/corsair-16gb-288-pin-ddr4-sdram/p/N82E16820236591?Item=N82E16820236591


Which option will be faster for a program (Stata) which loads all data to RAM and performs calculations?

Option 1: Use #2 only (4 slots, 64GB in total)

Option 2: Combine #1 (3 slots, 48GB) and #3 (2 slots, 16GB)

If I go for option 2, can I force my computer to always use the fast RAM, which is #3, as long as it does not have to use more than 16GB of RAM? If that is possible, option 2 should be faster than option 1, correct?
 
RAM speed is dependent on 3 things: of course the DRAM'a capabilities, but then also the processor which contains the memory controller on modern systems, and the motherboard which has to be compatible with the DRAM (DDR3 or DDR4), and the CPU and also typically limits the amount of DRAM you can use. You should also check DRAM compatibility with the motherboard, usually in the support section of the motherboard manufacturer.

You are not going to be able to mix DDR3 and DDR4 DRAM on the same motherboard.

No, you do not have control of which memory is used when.
 
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mujmuj

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@mdd1963 @thx1138v2

Thank you very much! I will buy a mother board that supports whatever fast RAM that I get. So that's not a big concern.

So I need to get DDR4 only.

Is it true that this is the fastest RAM on the market? It's very very expensive but it says "DDR4 5000 (PC4-50000)"

There are other cheaper verisons with "DDR4 4800 (PC4-38400)" Is this slower than "DDR4 5000 (PC4-50000)"?
 

mujmuj

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mujmuj

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You will need x299 chipset motherboard for this cpu.
x299 supports quad channel memory operation. So it's best to use quad channel kit with it (kit of 4 modules).

Thank you!

And yes this 299 thing is what I was considering.

But now I think I don't need 256GB RAM.

So I am considering motherboards that support 128GB RAM.

Among them, this one seems to be the best one.

https://www.amazon.com/dp/B07MBJ6N9D

But what makes it even more expensive than the one I was previously considering (that supports 256GB RAM)?

From reading specs, I can't tell.
 

EndEffeKt_24

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Maybe you should also get yourself some "hands-on" help from a co-worker, friend or family that is at least a bit more tech-savy. Generally everybody started ar some point to mess arround with his first build, but in your case its a 3000-4000 $ system.
 
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mujmuj

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All x299 boards with 8 ram slots support 256GB ram.
If you need 128GB, then just use 4x 32GB ram modules.

There are significantly less expensive x299 boards than that. It seems, like you're looking for most expensive of them.

I understand. Thank you.

And thanks to previous repliers I learned that it is impossible to install DDR3 and DDR4 in the same motherboard. But is it possible to install "DDR4 4800 (PC4-38400)" and "DDR4 5000 (PC4-50000)" in the same motherboard? If that is possible, on which RAM will my computer's speed depend? Slower one? So does it become pointless to have faster/expensive RAM?


Maybe you should also get yourself some "hands-on" help from a co-worker, friend or family that is at least a bit more tech-savy. Generally everybody started ar some point to mess arround with his first build, but in your case its a 3000-4000 $ system.

Thank you for your tip. All my friends are far from being tech savy but I will try more.
 
But is it possible to install "DDR4 4800 (PC4-38400)" and "DDR4 5000 (PC4-50000)" in the same motherboard?
Possible - yes. Recommended - no.
If that is possible, on which RAM will my computer's speed depend? Slower one? So does it become pointless to have faster/expensive RAM?
Will depend on slower modules. Plus - you may run into ram compatibility problems, when they refuse to run together at all. That's why, it is recommended to use kit of identical ram modules.
 
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EndEffeKt_24

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I am not sure whats the maximum supported RAM frequency on x299 if you populate 8 slots. I would guess the load for the mem controller of the cpu will be massive. Most of the very high RAM OCs are reached on ITX boards with short traces and only 2 dimms. I would not expect frequencies north of 3600 mhz on x299 with 8 dimms.
Maybe someone with x299 experience can shed some more light on that topic? I am just afraid you buy ram for 1000 $ and when you get the same performance for 500 $.
 
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mujmuj

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Possible - yes. Recommended - no.

Will depend on slower modules. Plus - you may run into ram compatibility problems, when they refuse to run together at all. That's why, it is recommended to use kit of identical ram modules.


Thank you so much. Thanks to your help, now I am narrowing down further and further.

Does GB size matter for speed?

Option 1 has lower level of "DDR numbers" but it contains more "GB" than Option 2 and 3.

But for Option 2 and 3, I will just buy twice as many modules so that all options have the same "Total GBs"

Which option would produce fastest computation? Again, I am willing to buy motherboard and CPU to support whichever is faster RAM. And what's different between 2.1 and 2.2, or 3.1 and 3.2?


<Option #1>

https://www.newegg.com/corsair-64gb-288-pin-ddr4-sdram/p/N82E16820236602

DDR4 3600 (PC4 28800), 32GB per module, 288-Pin, SDRAM

Buy 2 of these to have 64GB

<Option #2>

https://www.newegg.com/corsair-32gb-288-pin-ddr4-sdram/p/N82E16820236579
(Option 2.1)
https://www.newegg.com/corsair-32gb-288-pin-ddr4-sdram/p/N82E16820236238
(Option 2.2)
(What's the difference between 2.1 and 2.2?)

DDR4 4000 (PC4 32000), 16GB per module, 288-Pin, SDRAM

Buy 4 of these to have 64GB

<Option #3>

https://www.newegg.com/corsair-32gb-288-pin-ddr4-sdram/p/N82E16820236379
(Option 3.1)
or
https://www.newegg.com/corsair-32gb-288-pin-ddr4-sdram/p/0RN-001Y-003Y9
(Option 3.2)
(What's the difference between 3.1 and 3.2?)

DDR4 4133 (PC4 33000), 16GB per module, 288-Pin, SDRAM

Buy 4 of these to have 64GB
 
Which option would produce fastest computation? Again, I am willing to buy motherboard and CPU to support whichever is faster RAM. And what's different between 2.1 and 2.2, or 3.1 and 3.2?
Do not look for individual modules (or kits of 2 modules). Get kit of 4 modules (quad channel kit).
If you need 64GB ram total, then get 4x16GB kit.
If you need 128GB ram total, then get 4x32GB kit.

I'm not sure, how much STATA is impacted by ram speed.
From those options:
1. 3600 mhz CL18 - slowest;​
2. 4000mhz CL18 (2.1) - fastest, CL19 (2.2) - middle;​
3. 4133mhz CL19 - middle (faster than 4000mhz CL19). 3.1 and 3.2 is the same product.​
 
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mujmuj

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Do not look for individual modules (or kits of 2 modules). Get kit of 4 modules (quad channel kit).
If you need 64GB ram total, then get 4x16GB kit.
If you need 128GB ram total, then get 4x32GB kit.

I'm not sure, how much STATA is impacted by ram speed.
From those options:
1. 3600 mhz CL18 - slowest;​
2. 4000mhz CL18 (2.1) - fastest, CL19 (2.2) - middle;​
3. 4133mhz CL19 - middle (faster than 4000mhz CL19). 3.1 and 3.2 is the same product.​


Thanks again. I am so grateful. I also learned what CAS means thanks to you.

And by "kit" you just mean the number of modules in one item? So this is a kit of 2 modules and this is a kit of 4 modules?

And the reason why 4-kit module is recommended because they are faster? How does that affect speed.. I'd guess that's unlikely so you perhaps meant 4-kit module is cheaper?

I guess this is the fastest memory on the market? Right? It doesn't have 4-kit product though (if what I think "kit" means is right)