Question RAM Question (Dell Latitude 5400)

[CarbonLogic]

Hello everyone, I have got a refurbished Dell Latitude 5400 and its got 2 mismatched DDR4 SO-DIMMs

The original is a Samsung M471A1K43BB0-CPB (2133Mhz 8GB 1Rx8)

The refurbisher installed a second SK-Hynix HMA81GS6JJR8N-VK (2666Mhz 8GB 1Rx8)

The laptop has an i5-8365U and as per the product page on Dell, the laptop supports upto 32GB with a max ram speed of 2666Mhz.

Now, I am aware that with mismatched RAMs the computer will run at the max speed of the slower ram of the two, so it should be half of 2133 (1066.5) but CPU-Z is showing that its running at 665Mhz, this is confusing me is there something wrong? I have observed that once in a while it jumps to 1066 momentarily and then goes back to 665.





Also I have recently got my hands on G-SKill F4-3200C22S-8GRS (2 sticks of 8GB 3200Mhz) for dirt cheap. Its not kit but 2 separate sticks. I wanted to ask about this anomaly of 665Mhz before installing the new RAM sticks.

I know that the laptop will run the memory at 2666Mhz and not at 3200Mhz but its not really a loss for me because these sticks were cheaper than Crucial's 2666Mhz sticks. The only difference I think will be in the CAS Latency. Gskill is CL22 and Crucial's 2666 is at CL19 I believe, would that make significant difference?

Thank you!

 

[VirtualLarry]

Is the 3200 DDR4 1.35v (won't work) or 1.20V JEDEC (might work, if it has a 2666 profile)?

 

[CarbonLogic]

Is the 3200 DDR4 1.35v (won't work) or 1.20V JEDEC (might work, if it has a 2666 profile)?

Are you referring to the GSkill RAM? Yes those are DDR4 1.2v. I thought DDR4 never came with 1.35v requirement, werent those only with DDR3L?
Also what do you think about the DRAM Frequency running at 665?

 

[VirtualLarry]

Are you referring to the GSkill RAM? Yes those are DDR4 1.2v. I thought DDR4 never came with 1.35v requirement, werent those only with DDR3L?

99% of "gamer RAM" is 1.35V (overclocked, and over-volted by default).

There is a more recent standard 1.200V DDR4 for JEDEC 3200 Speed, that runs at CAS 22. Normal over-volted, runs at CAS 14/16/18.

Also what do you think about the DRAM Frequency running at 665?

Is it running without crashes? Then why change it?