Should I get DDR4-2400 or DDR4-2133?

[revzephyr]

I want to add some more memory(ram) to my laptop (dell inspiron 14-7460). The original ram installed is 1x8GB (DDR4-S.O.DIMM-2400) (Hynix HMA81GS6AFR8N)

According to the manual, the 2400 MHz memory works at 2133 MHz for the 7th generation Intel Core processors.

Does that mean if I put a 2400MHz, it will max at 2133Mhz? I want to change it into 2x8GB, should I get 2x8GB (DDR4-2400MHz) or (DDR4-2133Mhz)? (I am on a budget, so if I can save a little bit it will be better).

Thank you very much in advance.

 

[photonboy]

Regardless it doesn't matter, but it's best to get another IDENTICAL STICK or at least as close as possible to avoid potential issues.

Then test for a full pass (USB stick) with MEMTEST86 www.memtest86.com

You can see what the memory is currently at using CPU-Z from CPUID site. Under "memory" it should tell you its in single channel and report "1066MHz" if it's in 2133MHz (you need two sticks so its in DUAL CHANNEL to stay at 2133MHz).

*so adding ANOTHER STICK will double the bandwidth anyway and that's plenty for that system.

 

[photonboy]

http/www.ebay.com/itm/HMA81GS6AFR8N-UHN0AC-Hynix-8GB-PC4-2400T-SA1-11-for-Pavilion-27-A227C-All-/142508626683?hash=item212e2d12fb:g:0FgAAOSwujBZvEzx

 

[revzephyr]

Regardless it doesn't matter, but it's best to get another IDENTICAL STICK or at least as close as possible to avoid potential issues.

Then test for a full pass (USB stick) with MEMTEST86 www.memtest86.com

You can see what the memory is currently at using CPU-Z from CPUID site. Under "memory" it should tell you its in single channel and report "1066MHz" if it's in 2133MHz (you need two sticks so its in DUAL CHANNEL to stay at 2133MHz).

*so adding ANOTHER STICK will double the bandwidth anyway and that's plenty for that system.

So I should run CPU-Z with the current spec and see if it's in 2133MHz or 2400MHz? If it is 2133HMz, it means I can just get 2 DDR4-2133MHz instead?

 

[1shado1]

Regardless it doesn't matter, but it's best to get another IDENTICAL STICK or at least as close as possible to avoid potential issues.

Then test for a full pass (USB stick) with MEMTEST86 www.memtest86.com

You can see what the memory is currently at using CPU-Z from CPUID site. Under "memory" it should tell you its in single channel and report "1066MHz" if it's in 2133MHz (you need two sticks so its in DUAL CHANNEL to stay at 2133MHz).

*so adding ANOTHER STICK will double the bandwidth anyway and that's plenty for that system.

So I should run CPU-Z with the current spec and see if it's in 2133MHz or 2400MHz? If it is 2133HMz, it means I can just get 2 DDR4-2133MHz instead?

Just buy a stick that you were given a link to (2400MHz), so it matches the one you already have. Why would you want to buy 2 sticks @ 2133MHz and double the cost? Although I could very well be missing something here (old and semi-senile).

 

[photonboy]

1shado1,
That was my suggestion.

You want to have IDENTICAL sticks if possible.

*Note that memory sticks have different PROFILES for the frequency/CAS/etc setup. The 2400MHz stick is defaulting to the "2133MHz" profile likely anyway.

That doesn't mean you want a different 2133MHz stick though. For one thing the BIOS likely would default to the LOWEST profile anyway to ensure reliability.

Long story short, you should
1) Preferably get an IDENTICAL stick, or
2) if not available get one with the exact same FREQUENCY and CAS rating

Even if it drops to the LOWEST frequency profile having two sticks of memory with that CPU will still provide enough bandwidth so there would be no CPU bottleneck.