Issue with upgrading RAM on Lenovo w540

Naks

Naks

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Hi everyone,

I'm hoping someone here can help out with this issue I'm having with RAM upgrade.

I just inherited a w540 with the i7-4700MQ CPU, which had 7Gb RAM (3x2Gb + 1x1Gb RAM). The laptop is rated to 32Gb max.

I bought 4 x 8Gb ram, but the laptop won't recognise more than 16Gb. We tried different brands (Crucial, Kingston, Hynix), different sizes, different voltages, with no success. Even trying to put in 2 x 2Gb in the top slots to bring the RAM up to 20Gb doesn't work.

This is the RAM spec: Crucial PC3-12800 (800 MHz), 1.35v.

Can anyone share any suggestions on how to get the w540 to recognise more RAM?

Thanks
 
What OS you running and what version?

I know Win 7 Home Premium is capped at 16GB on 64bit.

So you will need to check what OS you have and what the cap is.
 
@pitbull the issue is the BIOS won't even load if we put the full 32Gb in. Running Win10 x64

@spiderz The Lenovo site specifies 1600, which the Crucial is.


I've been fiddling a bit more, and now it works with the 2x8Gb in the bottom slots and 2x2Gb in the top slots, so running with 20Gb now. But the 2Gb DIMMS are 667 MHz, so total RAM is running at 1333 MHz.

However, it really doesn't like the 8Gb DIMMS in the same row of slots, i.e., slots 1 & 2. It's fine when the DIMM is moved to either slot on the next row, which is odd?
 
Naks said:
However, it really doesn't like the 8Gb DIMMS in the same row of slots, i.e., slots 1 & 2. It's fine when the DIMM is moved to either slot on the next row, which is odd?
Click to expand...
Such behaviour suggests that it can only run these 8GB modules in dual channel configuration, which suggests that your modules are configured 1R8 (single rank). Check with CPU-z whether I am right.

Modules selling on the Crucial Website for this laptop are 2R8 (dual rank). It may be a limitation of the CPU that it require 2R8 modules to achieve full 32GB, I don't know, just guessing based on the limitations of older memory controlers, I didn't find detailed CPU specification.

Please post full model number of memory modules or attach a photo.
 
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Naks said:
yep, BIOS is the latest.

first thing I did was update all firmware via the Lenovo site.
Click to expand...
Did you DL the QVL?
Some machine are quite anal about RAM brands. Less nowadays than 7-8 years ago, but there are still a few.
It cannot do any harm if you go through the process of illimination
 
This memory should work. There is a different model on the Crucial Web site listed as compatible with your laptop, but it is also dual rank module, probably because the current model has changed (they got chips from different supplier).

I'd like you to compare JEDEC #6 timings (pic) with CPU-z 'Memory' tab. Does it match values? I want to check whether BIOS pickup correct SPD values. Does it show a dual channel operation on the same tab?

If SPD valules are matching, my guess is that there is a fault in CPU, traces on the motherboard are missing (it could be early model of the motherboard), or just a poor contact on the CPU socket. In the last case reseating CPU can help. You would need to replace cooling compound as well.
 
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Here is a screenshot of the memory tab:

RAM2.JPG


One thing I am noticing is that the NB frequency is mostly at 799Mhz, but sometimes jumps to much higher values for a split second - so far I have seen 1198, 2197, and 3295 Mhz.

I've removed the DIMMS and switched them around in the various slots, and now both 8Gb DIMMS are working in a single row! When we did that yesterday, the laptop just beeped and would not boot, so not sure what happened.
 
NB frequency is normal, it changes according to the current CPU speed. If you stress CPU, it will be stable at maximum (unless you experience thermal throttling).

It is strange that CPU do not clock the memory at maximum (1600MHz), but at the lower value 1333MHz using JEDEC #4 timing. If you stress CPU and this value (that says now 665.8MHz) do not change to 800MHz, it is something wrong. It is normal only if there are other (slower memory modules) in other slots. I suggest to reset BIOS settings to factory defaults and start over.
 
on another note, I can't seem to change any of the settings in the BIOS - things like the boot sequence, etc.

But there was not BIOS password setup on this laptop, so I'm a bit lost.

when it asks for the password, I just press Enter and can go into the BIOS .
 
Naks said:
on another note, I can't seem to change any of the settings in the BIOS - things like the boot sequence, etc.

But there was not BIOS password setup on this laptop, so I'm a bit lost.

when it asks for the password, I just press Enter and can go into the BIOS .
Click to expand...
Device settings are locked by remote management, I guess.
Unless some theft protection is active, you should be able to deactivate remote management. Look for Intel ME or Intel AMT. It can be available in BIOS setup or by a special key during boot.

The other cause can be fixed by reflashing BIOS or clearing CMOS: Power off. Remove power cord, remove battery. Press and hold power button for 30 second. Leave laptop for an hour and repeat a trick holding power button. Then reconnect power cord (but not a battery), power on and go to the setup resetting factory defaults.
 
@Naks , Hi Bud ,Have the same laptop with 4800mq and K1100m Graphics. Did the 4x8gb Ram Upgrade about a month ago and was smooth. Previous Factory install was 2x4gb .

After initial ram installation machine took around 2 minutes with just the power button lit up and no display on screen , after that booted into Windows 10 with no hassles.

Also using the 1.35v ddrl 1600mhz Kingston dimms.

Must say 32gb coupled with the quad core and dedicated graphics runs on par with most desktops I've used .Still using the Stock Standard 180gb Intel SSD that came standard with it..

Not sure if of interest to you but seems you can also upgrade the FHD TN panel to 3k for around 2k which I am contemplating..

If you in ever in JHB you welcome to bring the dimms so we can test in mine to isolate if it is indeed a ram problem or possibly a mobo issue.
 
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