Can Any sodimm users here offer clarification on performance?

[Andalusian]

To my disappointment there isnt much in the way of round ups for sodimm kit performances, whether its gskill or corsair, etc. The closest to tests I have seen is this article

https://www.tomshardware.co.uk/ddr4-sodimm-notebook-memory-roundup-review,review-34291-4.html

What I dont understand is what makes the dual rank outperform the single rank hyperx, which has significantly lower latency. In general, the article showed that going over 2666 mhz doesnt offer much benefit, which is the speed I intend to get since my 7700hq wont accept any higher speed. There is a dual rank hyper x at 16gb a chip, however it was not tested, only 8gbx2 dual channel kits. If anyone can offer clarification I would be grateful.

 

[Arjai]

From your linked article: (pertaining to dual-rank kits)
"In the end, once you’ve whittled down the memory modules that will work with your system, if you’re looking for the best balance of performance and price, our advice is (obviously) to make sure you’re running at least two SODIMM sticks (if at all possible) for the extra bandwidth that comes from doubling your memory channels. Then, to nudge the performance needle a little further forward, consider dense dual-rank kits with lots of integrated circuits, to increase the bandwidth even more."

This is what I run, dual channel, on my i5 ivy bridge laptop. I am unsure how much of an impact a dual-rank would have. Other than having more ram to use, that is. I am very happy with what I got, when I upgraded to dual channel, even as a single-rank.

 

[Andalusian]

From your linked article: (pertaining to dual-rank kits)
"In the end, once you’ve whittled down the memory modules that will work with your system, if you’re looking for the best balance of performance and price, our advice is (obviously) to make sure you’re running at least two SODIMM sticks (if at all possible) for the extra bandwidth that comes from doubling your memory channels. Then, to nudge the performance needle a little further forward, consider dense dual-rank kits with lots of integrated circuits, to increase the bandwidth even more."


This is what I run, dual channel, on my i5 ivy bridge laptop. I am unsure how much of an impact a dual-rank would have. Other than having more ram to use, that is. I am very happy with what I got, when I upgraded to dual channel, even as a single-rank.

I was always under the impression that duel rank always had less performance as thats what I was always told in the ddr3 days. Logic was that because there are double the dies, the latency increases and frequency is limited. What really got me in that regard was how the hyperx was always scoring worse over gskill because it was single rank, even with less latency. I really dont see any reason why not to go for either hyperx 16GBx2, or the gskill 8GBx2, but I wished they had others to compare like crucial ballistixc and corsair vengeance. Hopefully someone with both here can weigh in.

 

[cadaveca]

I was always under the impression that duel rank always had less performance as thats what I was always told in the ddr3 days. Logic was that because there are double the dies, the latency increases and frequency is limited. What really got me in that regard was how the hyperx was always scoring worse over gskill because it was single rank, even with less latency. I really dont see any reason why not to go for either hyperx 16GBx2, or the gskill 8GBx2, but I wished they had others to compare like crucial ballistixc and corsair vengeance. Hopefully someone with both here can weigh in.

You were misinformed. dual-rank memory was/is slower because it presented more load on the memory controller, limiting the max frequency possible. The same applies to DDR4 too. You can offset this loss by using four sticks instead of two though, so there's a fair bit of stuff about this that many users are not aware of. I was posting that four sticks were better than two for a long time and it wasn't until recently that those that do extreme benchmarking started to agree. I guess I'm just that far ahead of the curve.

I'll have a Team Group SODIMM review coming in the future, and I've already tested and posted a G.SKILL kit.

 

[Andalusian]

You were misinformed. dual-rank memory was/is slower because it presented more load on the memory controller, limiting the max frequency possible. The same applies to DDR4 too. You can offset this loss by using four sticks instead of two though, so there's a fair bit of stuff about this that many users are not aware of. I was posting that four sticks were better than two for a long time and it wasn't until recently that those that do extreme benchmarking started to agree. I guess I'm just that far ahead of the curve.

I'll have a Team Group SODIMM review coming in the future, and I've already tested and posted a G.SKILL kit.

Is that gskill kit a sodimm kit?

Well my laptops maximum supported frequency is 2666 according to my ODM, so going past that doesnt offer any benefit since it would literally just down clock. What do you make of the toms hardware roundup?

https://www.tomshardware.co.uk/ddr4-sodimm-notebook-memory-roundup-review,review-34291-4.html - this is all dual channel too.

They show that the 2666mhz 8GBx2 gskill outperforms the 2666mhz 8GBx2 hyperx 2666, and their reasoning for that is the duel rank setup of the gskill gives a performance edge, while the hyperx single rank doesnt because of that, even if it has significantly lower latency timings of 15-17-17.

The really fast sticks that are over 3200mhz all use single rank as you implied in regards to speed, though only gskill seems to offer that speed in sodimm. Test shows that it did not outperform a non dual rank setup of 2666mhz, even with xmp. So this further adds to the confusion if you see where I am going with this.

unfortunately my laptop only has 2 slots, my general logic do keeping to that was that getting a 4 slot like a high end clevo meant significant cost at minimal gains, and its not like 4 slots would equal quad channel.

Both corsair, gskill, hyperx and crucial claim to "auto over clock", and if that was the case, the test didnt show that, but I really dont know. Crucial claims ram makers tend to lie about their performance with latency, and hyperx is proving that.

So in theory then, would the low latency dual rank hyperx 2666 xmp outperform the gskills in the setup? That is my logic, however there is obviously more too this. What do you recommend?

 

[cadaveca]

You really need to check what your laptop supports. They are usually pretty specific, so I can't make a general recommendation here, unfortunately. I'd love to be able to tell you exactly what to buy, but can't.


My review of the G.SKILL SODIMMs is here:

https://www.techpowerup.com/reviews/G.SKILL/Ripjaws_DDR4_SODIMM/

 

[Andalusian]

You really need to check what your laptop supports. They are usually pretty specific, so I can't make a general recommendation here, unfortunately. I'd love to be able to tell you exactly what to buy, but can't.


My review of the G.SKILL SODIMMs is here:

https://www.techpowerup.com/reviews/G.SKILL/Ripjaws_DDR4_SODIMM/

Gonna look this through, do you have a suggestion ram wise? They only said higher then 2666mhz wont work. I know certain brands have CL requirements, or even brand QVL, but this laptop doesnt have it, the Mech-15hs.

 

[cadaveca]

Gonna look this through, do you have a suggestion ram wise? They only said higher then 2666mhz wont work. I know certain brands have CL requirements, or even brand QVL, but this laptop doesnt have it, the Mech-15hs.

So this is likely to a chipset limitation. checking the laptop specs, this makes sense of what they tell you about 2666 MHz max, but on the product page it says 2400 MHz max, so I'm a bit confused...

 

[Andalusian]

So this is likely to a chipset limitation. checking the laptop specs, this makes sense of what they tell you about 2666 MHz max, but on the product page it says 2400 MHz max, so I'm a bit confused...

I had called them and asked, they said that 2400mhz is just the stock ram, but 2666mhz is supported. Doing a little research on the i7-7700hq, it appears no one is able to get past 2666mhz with it, so thats why its the choice speed, and Max frequency isnt the goal for the this reason.

I'm also a bit confused when you said dual rank is slower then single rank ram. Did you mean that in regards speeds over 3200mhz? The testing from toms hardware showed that in the speed of 2666mhz, dual rank is faster then single rank ram. User Arjai said that dual-rank kits have lots of integrated circuits to increase the bandwidth even more, and im assuming dual rank performs betters at lower frequencies, while single rank does better for higher frequencies, such as around 3800mhz.

This review compares the ballistix sodimm to the hyperx. The board is a NUC, so it doesnt have the performance of the asrock you tested the gskill on.

http://www.legitreviews.com/crucial...400mhz-ddr4-sodimm-memory-kit-review_182281/4

 

[cadaveca]

I had called them and asked, they said that 2400mhz is just the stock ram, but 2666mhz is supported. Doing a little research on the i7-7700hq, it appears no one is able to get past 2666mhz with it, so thats why its the choice speed, and Max frequency isnt the goal for the this reason.

I'm also a bit confused when you said dual rank is slower then single rank ram. Did you mean that in regards speeds over 3200mhz? The testing from toms hardware showed that in the speed of 2666mhz, dual rank is faster then single rank ram. User Arjai said that dual-rank kits have lots of integrated circuits to increase the bandwidth even more, and im assuming dual rank performs betters at lower frequencies, while single rank does better for higher frequencies, such as around 3800mhz.

This review compares the ballistix sodimm to the hyperx. The board is a NUC, so it doesnt have the performance of the asrock you tested the gskill on.

http://www.legitreviews.com/crucial...400mhz-ddr4-sodimm-memory-kit-review_182281/4

yes, at the same speed, dual-rank offers more performance. But single-rank can scale the MHz up to offset those losses, or you can use 2 sticks per channel to get the same effect. This is also reflected on AMD platforms, that need single-rank memory to scale up past 2666 MHz or so. It's just more capacitive load on the memory controller with dual-rank sticks.

It seems quite often that SODIMMs do not use XMP profiling. So that's what you should be looking for.. a set that does not use XMP, IMHO. There are some interesting SOMDIMM kits out there, like the HyperX kits @ 2133 MHz, with 13-13-13 timings. Naturally, it'd be best if the laptop maker gave you a list of supported DIMMs, or if you found a forum with many users of this laptop so you could compare what works, really, since sometimes the sub-timings of sticks differ, which can affect stability.

 

[Andalusian]

So far, the one that even shows its xmp and deep specs is the kingston. Gskill, corsair, crucial all say xmp, but no specs past that. This kit seems the best choice just on paper, but what do you think in regards to sub timings?

https://www.kingston.com/dataSheets/HX426S15IB2K2_32.pdf

I would rather have the crucials at 16-18-18 at 2666mhz since its cheaper dual rank 8gb chips, but that only works with xmp, and my laptop doesnt have that in bios, and gskill is sold out everywhere, and has CL of 18-18-18.