Lenovo T520 Maximum Memory: Not 8, But 16 GB!

Contrary to what Lenovo wants to make you believe, the T520 laptop is not limited to 8 GB of RAM. I own this reliable workhorse and made the mistake of buying another laptop because I wanted something more elegant, but mainly because I need more than 8 GB of RAM. As it turned out, the other machine was not as business-proof as I thought.

Since I had bought an 8 GB module for the other machine I decided to try it in the T520 – it worked instantly and flawlessly with 12 GB in total. That gave me confidence to order a second 8 GB module and replace the remaining 4 GB SO-DIMM with it. Now my T520 is at 16 GB of RAM, twice the amount Lenovo’s specifications state as the maximum.

If you own the T520 and want to extend your machine’s life: spend 80 € for two 8 GB SO-DIMMs and upgrade to 16 GB. If you want to go a little bit further, replace the hard disk drive with an SSD. I can recommend the Plextor M3 Pro and the Samsung SSD 840 Pro (I own the Plextor since the Samsung was not yet available).

I did both, upgraded the RAM and replaced the HDD with an SDD, and the laptop’s new power nearly scares me. Working with virtual machines now is actually fun – it definitely was not, before.

For the record: the SO-DIMM model I used is the Kingston M1G64J90 (8 GB DDR3-1333).

, ,

23 Responses to Lenovo T520 Maximum Memory: Not 8, But 16 GB!

  1. jim May 31, 2013 at 10:04 #

    Which T520 do you have? I have read that this works on I7 with quad core, but not the I5 dual core.

    • Helge Klein June 4, 2013 at 09:08 #

      I have an i5-2520M with 2 cores.

    • William July 25, 2016 at 08:42 #

      I have upgrading my T520 to windows 10 professional, but install the newest bios first. Download also all new Lenovo downloads. Then you can install 2x8Gb memory Kingston KCP313SD8/8.

    • Wesley Shelten October 28, 2018 at 22:28 #

      it is max memory per slot not maximum memory

  2. jim August 14, 2013 at 01:46 #

    Thank you.

  3. Austin August 21, 2013 at 04:40 #

    Interesting. I have a T520 (423946U) ….with 4GB in one slot and the other slot is empty. I think I’ll order up an 8GB to put me to 12. Any reason this shouldn’t work?

    Thanks for this fun post and nice write up …and very nifty good news!!


  4. martin December 13, 2013 at 18:59 #


    I searched for the specific memory model number on amazon and found this review: http://www.amazon.com/Memory-Lenovo-ThinkPad-DDR3-1333MHz-204-pin/product-reviews/B008O525LU/ref=pd_sim_sbs_pc_cm_cr_acr_img_1/192-5524414-6986460

    Did you have similar errors using that chip? Are you using 2x the same model?

    Thanks! Martin

    • Helge Klein December 13, 2013 at 20:41 #

      Yes, I have two similar modules. And no, I have no errors at all, and I use the system heavily.

      • martin December 13, 2013 at 22:51 #

        Thank you for the quick reply. I will order two of them :) I love my T520. Thanks for sharing your experiences!

        • ace November 20, 2015 at 15:24 #

          Hey martin did u have any problems aftere using 8gb *2 ram upgrade ??

  5. Joji September 19, 2014 at 17:55 #


    The amount of memory supported is decided by the chipset installed in the machine. As per Lenovo, T520 uses Intel 2nd Generation i5 & i7 processors. According to Intel below are the maximum memory supported by each of those processors:

    Intel® Core™ i7-2620M Processor (4M Cache, up to 3.40 GHz) — Maximum memory of 16 GB (dependent on memory type)
    Intel® Core™ i7-2630QM Processor (6M Cache, up to 2.90 GHz) — Maximum memory of 16 GB (dependent on memory type)
    Intel® Core™ i5-2540M Processor (3M Cache, up to 3.30 GHz) — Maximum memory of 16 GB (dependent on memory type)
    Intel® Core™ i5-2520M Processor (3M Cache, up to 3.20 GHz) — Maximum memory of 16 GB (dependent on memory type)
    Intel® Core™ i5-2410M Processor (3M Cache, up to 2.90 GHz) — Maximum memory of 16 GB (dependent on memory type)

    Hello Martin:

    Can you please share the details if the memory upgrade worked for you.


  6. dekosuke January 26, 2015 at 16:56 #

    hello there,

    I bought a T520 4242RU2 model on 2013.
    It was slow machine as you said.

    I changed RAM 2GB to 4GBx2
    also replaced SSD 128GB Kingston instead of 320GB HDD
    clean install 64bit windows 7 ultimate instead of 32bit windows 7 pro
    replace CPU from i5 2540M to i7 2720QM
    LCD monitor HD to FHD 1920*1080 AUO

    It has nice performance now like bullet train Shinkansen (japan)
    and pretty good keyboard which I like.

    would like to try 16GB RAM for next.

    Thanks for nice information.


  7. titrisol April 16, 2015 at 17:54 #

    Thanks for the info, 16GB improved the speed of Matlab, and other number crunching significantly… SSD is next

  8. Alan Coleman October 26, 2015 at 17:52 #

    I’ve just upgraded one of the slots on my T520i after reading this article. I used the following RAM: Kingston Memory Module / 8 GB / DDR3 / 1333 MHz / soDIMM

    No problems at all!

  9. kent Mossin November 3, 2015 at 13:19 #

    It Works good and its a fast PC now.. I also put af 500GB SSD EVO in.

  10. Alan Coleman November 30, 2015 at 13:15 #

    If anyone is interested I have documented my own successful experience with this process, including the SSD upgrade. http://www.alancoleman.co.uk/blog/2015/11/lenovo-t520i-ram-and-hard-drive-upgrade/

  11. Ryan W December 12, 2015 at 16:17 #

    Another undocumented upgrade you can make is putting an mSATA SSD in the WWAN (cellular card) slot, then you can keep your existing HD for extra storage. For their age these are still VERY useful laptops.
    if you want to get super carried away the CPUs are socketed and can be upgraded, I’ve heard rumors you can even use the next generation i5/i7 CPUs with upgraded graphics in them after flashing to the latest BIOS.

  12. maras61 March 13, 2016 at 23:36 #

    Successfully tested with Team Group Elite TED3 16G 1333C9DC-S01,
    SO-DIMM DDR3, 2x8GB, DUAL, 1333MHz, CL9, 1.5V,

    ThinkPad T520,
    model 4242A14,
    Bios 8AET65WW(1.45) 05/14/2015,
    Win7Pro 64bit.

  13. Paul D Mallett August 17, 2017 at 11:37 #

    This got me thinking…. my T520 which is running Debian 8 works well enough for most things but falters when using Windows in VirtualBox so I took a look at the CPU – Version: Intel(R) Core(TM) i7-2720QM CPU @ 2.20GHz and it appears it will support — Maximum memory of 32 GB (dependent on memory type) if you can afford it. I think 16GB will do for the moment. Thanks for the tip.

  14. Mateusz August 18, 2017 at 10:55 #

    Encouraged by this article, I decided to give it a try and I bought 2x 8G RAM chips for my venerable T520, and I am very pleased with the result. My 6-years old T520 flies again! The entire 16GB or RAM are perfectly detected and my VMs are extremely happy.
    It is a T520 based on a i5-2450M CPU @2.50 GHz. The chips I bought are referenced as Kingston’s KVR13S9K2/16 (SODIMM DDR3, PC3 1333 MHz, CL9)

  15. Sergey Ponomarev December 10, 2018 at 17:18 #

    Just checked for sure and 2x16Gb doesn’t work as expected. So installed two by 8Gb and now I have 16 GB – it works well.

  16. Jeff April 16, 2019 at 08:25 #

    I have a Thinkpad T520 with Windows 7 Professional, 64-bit operating system, an I5-2540M CPU @ 2.60GHZ with 8GB of Ram (2x4gb). After reading these posts I ordered 16GB (2x8gb) of ram from amazon the brand was Timetec. On April 13, 2019 I first put one stick in the easy to get at bottom and system showed 12gb. Then I lifted the keyboard and put the second stick in and system shows all 16gb. I also added a new ssd and everything is running great. I appreciated the info others wrote and thought I should post my results.

  17. Z May 28, 2019 at 08:15 #

    I have a t520, upgraded from the stock i5-2520M to the i7-2860QM which works fine but can run pretty hot under load. Also upgraded to 16GB ram (2 x 8GB modules), added an MSATA SSD, swapped the optical drive with a SATA hdd adapter for a total of 4TB spinning disc storage, and upgraded to an AC wifi/bt card; all works fine. I’m using a modded BIOS with the whitelists removed so I can use any half-size mini-pcie wifi card, and a few other features, this thing is awesome for such an old laptop now. the dude that made the modded BIOS told me it adds support for 16GB ram, but I’ve heard from others that have used the same modded BIOS that they now have support for 2 x 16GB sticks for 32GB total. I was skeptical but now that I see here that 2 x 8GB sticks was supported without a modded BIOS I’m inclined to try it.

    Does anyone know which DisplayPort version the t520 supports? Buying a 4K TV & wondering if I can connect the t520 to it at 4k resolution. Don’t care if it’s only 30Hz, I’d only use it to play 24/30FPS video files anyway. I’m not even sure this thing can handle decoding 4k HEVC files.

Leave a Reply