T520 16GB RAM upgrade questions

From what I've read on NBR you indeed can put 16GB of RAM in T420, so it should be possible for T520. Currently I have a 8 GB Crucial (2x4GB) Kit of 1333MHz RAM installed in my T520.

A few questions have come to mind after doing some online shopping:

1) Can T520 support 1600 MHz RAM and would this provide a speed boost over the 1333MHz I have already?

2) I see there is a 1.35 volt kit available from Crucial that is 1333MHz. It is a bit more expensive than even the 1600MHz RAM. My current RAM is 1.5 volt. Would this be supported by the T520 and provide more battery life/efficiency and therefore desired over the 1600MHz or 1333MHz 1.5 volt RAM?

3) Should I just play it safe and get a 16GB kit with 1.5 volt RAM and 1333MHz speed?

Thanks. Let me know what you think.

 

1.- Yes, memory bandwidth will be greater. On the other hand, though, you won't notice any difference in performance: if you use integrated graphics for gaming, you may notice a very small FPS improvement (because integrated graphics depend on system RAM).

Personally, I'd go with whatever's cheaper.

2.- Not entirely sure, but I believe it will work. You might want to wait for a Tx20 owner to confirm on this one, though.

3.- That wouldn't hurt.

 

3) That's the way to go for your T520:

​

DDR3-1600 is only available with the i7 quad-core on the W520:

​

2) The 1.25v RAM would be run at 1.5v anyway. Why spend more?

1) No speed boost.

 

Thanks for the replies.

@Kaso on your document it claims 8GB max, so is 16 GB not possible on the T520?

 

That's what the Lenovo tabook stated at the time of publication. Later in 2011, when T520 CTO options began to allow for quad-core i7, 16GB (2x8) RAM have been possible on such configurations.

 

I have 16GB in the T420 I am typing this on.

 

1.35V (not 1.25V) memory runs at 1.35V on my X220 and should run at 1.35V on any sandy bridge CPU.   i've yet to see evidence to the contrary.

now, whether there's a benefit is debatable.   battery life savings is marginal at best but LV memory does run slightly cooler.   under heavy load, surface temps are identical with 1.5V modules measured with an IR temp gun.

 

Me too, although I did the Core i7 2720QM upgrade for my T420 so I get the full speed of any ram chips I decide to buy.

 

The Kingston HyperX 1600MHz RAM in my T420s with i5-2520M CPU thinks it is running at 1600MHz

The test results I published here suggest there is a slight increase in performance.

I tried some 1.35V RAM in my T420s and couldn't seen any detectable change in power consumption. Then I saw this article which indicates that 1.35V support is a new feature of IvyBridge. Which suggest that SB hardware may recognise the 1.35V modules as being able to run at 1.35V but actually runs them at 1.5V because it is unable to step down to 1.35V.

John

 

That is possible. While Lenovo states what it officially supports, the users are free to apply upgrades to parts. However, reports on device characteristics may not always reflect actual operations.

I believe that is the case.

 

if your i5-2520M didn't step down to 1.35V then maybe only the ULV procs can handle LV memory at lower voltage.   my ULV X220 shows 1.35V so i don't think that anandtech article can be applied to all mobile SB procs.   if it were unable to step down then i'd hope my hwinfo64 screenshot below would show 1.5V, not 1.35V as it does.

plus, i have three 8GB 1.35V RDIMMs in my thinkstation C20 (xeon X5675) and know with certainty that older architecture supports it.   LV memory support isn't a new feature in ivy bridge.

the only limitation i'm seeing with the i5-2537M is that memory is stuck at 667MHz rather than 800MHz.   but, that's inconsequential for my needs.

 

^^^ The software may be reporting just the SPD specs and not the actual operational voltage.

Same software reports my Crucial M4's SATA 6.0Gb/s characteristic on the T510 (previous generation). Is the SSD operationally accessed at that speed?

Officially, both Intel and Lenovo have not claimed that their products support DDR3L (whereas, say, AMD has claimed that its Llano notebook APUs support DDR3-1600 and DDR3L-1330, making it clear on both speed and voltage capabilities).

 

looks like you're right.   the latest intel mobile SB datasheet ( link) says "Interface does not support ULV/LV memory modules or ULV/LV DIMMs."

in that case hwinfo64 is rather misleading.

i know with 100% certainty that current thinkstations support 1.35V.   i'm surprised intel decided not to carry that forth in sandy bridge given that it's quite a bit newer than westmere server/workstation architecture.

 

Desktop processors, chipsets and motherboards tend to be more "advanced" than their mobile counterparts.

Good discussions, though.

 

Thanks all for the responses. Two more questions:

1) would I be able to recycle my PC3-10600 RAM from my T520 into my Dad's Sony VAIO? I checked his system and it uses PC3 8500

2) whats the difference between PC3 10600, PC3 10660, and PC3 10666 if they are all 1333 MHz?

 

Most likely yes but depending on the hardware the RAM may clock down to PC3 8500 speeds in which most scenarios are likely to be unnoticeable.

Many RAM manufacturers tend to round up the peak bandwidth numbers differently hence the variation of 10600, 10660, 10666 etc. But in essence they are roughly the same to each other.

 

Ready to pull trigger on the RAM. is any brand better than the other or should I go for the cheapest? some options on new egg are g.skill, corsair, patriot and mushkin (although the last 2 are out of stock currently)

 

Go for the cheapest that comes with a lifetime warranty. All the manufacturers use the same few memory chip suppliers, so they're more or less the same. Price differences outside of specs is purely based on the "name."