G750 Upgraders: 1.35V memory is required!

[X-ROG]

Please note we fit 1.35V memory into our G750s. New Haswell CPUs require this and using 1.5V memory can cause problems along the lines of:

> Overheating
> Damage to the CPU IMC (due to the increased potential difference)
> Greater battery use than our stated values.

Also remember for every DIMM you add you increase the power consumption by 1-3W each, depending on what you buy.

Once I get ahold of a G750 to borrow for a few days I'll do an upgrade guide.

[hmscott]

taz2taz2taz2 wrote:
So I decided to upgrade the ram on my 750JW. Figured I'd remove the pre-installed two 4gb Samsung sticks and go for 16GB G.Skill Ripjaws DDR3 2133MHz.

Such a headache to open the laptop to get to the two slots under the keyboard, got aluminium cuts on my fingers along the way. Anyway after two hours of taking apart and putting back together, losing screws, working out which one goes where it was complete.

XTU scores before and after the ram upgrade, was 664 and is now 837. Nice little jump with no other system setting changes. I haven't had a chance to run any other tests but no doubt this will suffice for a while. From all the reading I have done, as I understand, the max I can go is 16gb with 2133Mhz SO-DIMMs.

If so the next time around, I may need to swap out for 1866Mhz (not sure if 32gb works). So far so good though and well worth upgrading the ram purely on the basis of getting the most out of this gaming machine.

taz2taz2taz2, great score bump, not many up-graders to 2133mhz have done before / after tests - thanks! 🙂

The G750 / G751 will support 4 x 2133mhz SODIMM's, and before those came out the 1866mhz SODIMM's x 4 in the G750JX - should work in all of the G750/G751's.

The key to getting all 4 x 8GB @ 2133mhz is to buy a matched set of 4 to start. G.skill offers 4x and 2x sets of 2133mhz and 1866mhz.

Someone did report using 2 x 2x8GB 2133mhz kits - you might try ordering another 2x8GB 2133mhz set from the same place you got those - you might get the same batch to potentially match.

16GB might be enough for most people, but with VM's getting populat - hosting images for testing - more memory will likely be helpful in the future. I occasionally don't watch myself and end up close to the edge of 32GB.

[taz2taz2taz2]

Ahh, I'm sure I read somewhere that 4 x 2133mhz didn't work. Maybe they didnt buy the matched pack of 4 SO-DIMMs. Then again even if I was sure it would work, paying £300 for 32gb ram would need to make a significant difference for me to jump for it.

I'm starting to use vm's for testing and work purposes which is the main reason why I upgraded. You must have turned off page filing etc to eat up 32gb! Either that or loads of vm's running at the same time.

It's nice to see me on the top of XTU points board on HWBOT for the G750JW. She's still got life yet, even though there's a struggle with games like MK10.

[Light]

I've had no issues using 2 kits of 2133MHz in all 4 slots. I've also tested using the harder to reach internal slots with 2 x G.Skill Ripjaws DDR3 2133MHz and the easy to reach slots with 2 x Kingston HyperX Impact 2133MHz., all run at 1.35v.

The memory performance was marginally faster using 4 x G.Skill Ripjaws DDR3 2133MHz compared with mixing 2 x Ripsaw and 2 x Impact but they run quite happily together.

[hmscott]

Light wrote:
I've had no issues using 2 kits of 2133MHz in all 4 slots. I've also tested using the harder to reach internal slots with 2 x G.Skill Ripjaws DDR3 2133MHz and the easy to reach slots with 2 x Kingston HyperX Impact 2133MHz., all run at 1.35v.
The memory performance was marginally faster using 4 x G.Skill Ripjaws DDR3 2133MHz compared with mixing 2 x Ripsaw and 2 x Impact but they run quite happily together.

taz2taz2taz2 wrote:
Ahh, I'm sure I read somewhere that 4 x 2133mhz didn't work. Maybe they didnt buy the matched pack of 4 SO-DIMMs. Then again even if I was sure it would work, paying £300 for 32gb ram would need to make a significant difference for me to jump for it.
I'm starting to use vm's for testing and work purposes which is the main reason why I upgraded. You must have turned off page filing etc to eat up 32gb! Either that or loads of vm's running at the same time.
It's nice to see me on the top of XTU points board on HWBOT for the G750JW. She's still got life yet, even though there's a struggle with games like MK10.

taz2taz2taz2 wrote:
Arghhh wth, I could have placed an order for the HyperX's which are sold cheaper than the rare G.Skills here in the UK. After all the reading I did, I thought the only sure bet was the G.Skills sticks.
Ah well, thanks for the heads up Light, noted if I get the urge to upgrade 🙂

Guys, the problem with mixing memory is the non-deterministic nature of the results. You can't be certain there aren't correctable errors going on causing retries and resulting in lower performance.

On top of that some tasks won't respond well to those delays when error correcting, when timing has been measured and resolved the processes expecting precise timing will fail on the late results.

I have had situations where clients have mixed memory, and the system BIOS utilities and OS utilities that give you memory information give you incorrect results, programs seem to run, until certain software runs for extended periods of time, and get anomalous results - what was the cause?

Most of the time the people that upgrade the memory, aren't in contact with the people that run the jobs - there is no connection to provide a reason for the software people to question the hardware - and they will waste a lot of time trying to debug the problem through the software - which doesn't work.

It's best to not mix memory, and if you do and you find any anomaly with the result, fix the memory mismatch immediately, before the problem snowballs through into software problems.

taz2taz2taz2, if you want to expand to 32GB, I would recommend contacting G.skill and request a trade in for your 2x 8GB for a set of matched 4x 8GB, and see if they can work something out for you. 🙂

G.skill Contact Us
http://www.gskill.com/en/contact

[taz2taz2taz2]

Arghhh wth, I could have placed an order for the HyperX's which are sold cheaper than the rare G.Skills here in the UK. After all the reading I did, I thought the only sure bet was the G.Skills sticks.

Ah well, thanks for the heads up Light, noted if I get the urge to upgrade 🙂

[Light]

I hear what you're saying hmscott and agree that using the same memory is the best option as long as it's possible to purchase the same memory.
The problem we have here from time to time is it is not always possible to purchase G.Skill Ripsaw 2133 MHz memory (due to supply shortages) so a suitable alternative was found to be the Kingston HyperX Impact 2133 MHz (more widely available) which has a wide range of compatibility functionality.

The HyperX Impact 2133 MHz SODIMMs and G.Skill Ripsaw 2133 MHz SODIMMs have enough built-in smart technology to make them compatible with a wide range of installations. As long as the MHz speed is the same they will happily co-exist, any differences in latency etc. is compensated for within the internal smart technology.

I have used HyperX Impacts 2133MHz in 2nd gen Intel processor laptops that were originally only meant to run 1333 MHz SODIMM, the resulting performance improvements were staggering, with 100% stability and no error issues.

Here is a useful article worth reading. It's not about mixing memory but it helps explain some of the performance issues surrounding non-ECC etc.
http://www.techspot.com/article/845-ddr3-ram-vs-ecc-memory/

[hmscott]

Light wrote:
I hear what you're saying hmscott and agree that using the same memory is the best option as long as it's possible to purchase the same memory.
The problem we have here from time to time is it is not always possible to purchase G.Skill Ripsaw 2133 MHz memory (due to supply shortages) so a suitable alternative was found to be the Kingston HyperX Impact 2133 MHz (more widely available) which has a wide range of compatibility functionality.

The HyperX Impact 2133 MHz SODIMMs and G.Skill Ripsaw 2133 MHz SODIMMs have enough built-in smart technology to make them compatible with a wide range of installations. As long as the MHz speed is the same they will happily co-exist, any differences in latency etc. is compensated for within the internal smart technology.

I have used HyperX Impacts 2133MHz in 2nd gen Intel processor laptops that were originally only meant to run 1333 MHz SODIMM, the resulting performance improvements were staggering, with 100% stability and no error issues.

Here is a useful article worth reading. It's not about mixing memory but it helps explain some of the performance issues surrounding non-ECC etc.
http://www.techspot.com/article/845-ddr3-ram-vs-ecc-memory/

Light, yes the memory I was referring to in my example was ECC memory, with different side effects than you are seeing with mixed DDR3 memory - the drop in throughput is similar but also indeterminate depending on how the memory is allocated.

I do understand the need to make do with what one has, but maybe you can sell 1 or the other set and get another set that matches what you keep?

.In the case of large numbers of upgraded memory, across hundreds / thousands of machines that are now acting up due to mixed memory, the solution is simple but time consuming. Pull all the memory that doesn't match in each CPU card, and sort them so they do match. Quite often it is only 2 or 3 mixed types striped across many machines.

You just need to pull the differing memory and match them in each card. Then the problems go away.

It is easier to figure that out the first time through, pulling all the memory and filling up with the new memory to start, to build up a pile of the old / same memory to start filling up the remaining CPU cards, matching memory make/model in each instance.

Glad to hear the mix works for you now, but be aware somewhere down the road it might come to bite an app, or not - we don't know for sure 🙂

[X-Gear]

Hello good people,

I currently have three of these in my stock G751JY as noted by ROG CPU-Z and a visual inspection:


Samsung 8GB PC3-12800 DDR3-1600MHz CL11 Chip Notebook Memory M471B1G73DB0-YK0



Taking into account the good advice here to match memory I am looking to buy the below memory that I've found on Amazon Prime (Prime & U.S. seller being a requirement):


Samsung 8GB (PC3L-12800) DDR3L 1.35V 1600 204-Pin SoDimm Laptop Memory Module M471b1g73bh0-yk0

To your knowledge will I fair ok and am I correct in thinking that adding a forth dimm will be advantagious overall as I will be putting it in dual channel?


James

[hmscott]

X-Gear wrote:
ello good people,

I currently have three of these in my stock G751JY as noted by ROG CPU-Z and a visual inspection:

Samsung 8GB PC3-12800 DDR3-1600MHz CL11 Chip Notebook Memory M471B1G73DB0-YK0

Taking into account the good advice here to match memory I am looking to buy the below memory that I've found on Amazon Prime (Prime & U.S. seller being a requirement):

Samsung 8GB (PC3L-12800) DDR3L 1.35V 1600 204-Pin SoDimm Laptop Memory Module M471b1g73bh0-yk0

To your knowledge will I fair ok and am I correct in thinking that adding a forth dimm will be advantagious overall as I will be putting it in dual channel by adding a forth strip?

James

{Admittedly posted this question in another thread. A bit anxious to pick this up}

X-Gear, the whole point of finding out the exact model number using CPU-Z is to use that exact model number, and purchase that - not something else/close 🙂

Those part numbers doesn't match exactly.

Here is a google search using the exact M471B1G73DB0-YK0 part number:

https://www.google.com/search?q=M471B1G73DB0-YK0&ie=utf-8&oe=utf-8

Every letter and number needs to match to get the same memory.

You should be able to find what you are looking for if you do a little more searching.

Please let us know what you end up getting 🙂

[Blackwind]

i have 32GB of memory running at 1600mhz. Is the upgrade to 2133mhz worth it?