Welcome to our peer-to-peer forums, where owners help owners. Need help now? Visit eSupport here.

English Community

ThinkPad NotebooksThinkPad: T400 / T500 and newer T series Laptops
All Forum Topics

2 Posts



13 Signins

42 Page Views

  • Posts: 2
  • Registered: ‎06-16-2011
  • Location: Algeria
  • Views: 42
  • Message 1 of 4

SoS Girl : T420 XP Windows

2011-06-16, 16:46 PM

T420 4178-6wU


I request XP Windows Downgrade from Lenovo South africa, and they send it to me, i recovered my laptop, and when i ceck in windows system property i get just 3.84 Gb of memory, and me, Ihave 8Gb installed with Nvidia Extwrnal graphic card (1Gb) already installed.

so can you tell me what happen ?

FYI, before when i use Win & i havn't this problem.



7262 Posts


United States of America

17929 Signins

168595 Page Views

  • Posts: 7262
  • Registered: ‎10-29-2009
  • Location: United States of America
  • Views: 168595
  • Message 2 of 4

Re: SoS Girl : T420 XP Windows

2011-06-16, 17:30 PM

Windows XP can only see approx 4GB of memory regardless of how much RAM is actually in your system.  You can confirm this with Microsoft.


If you want to use more than 4GB of memory, then you'll have to use a different operating system.


This has been discussed thousands of times so if you want more information please search the forum or google.


987 Posts


United States of America

592 Signins

14800 Page Views

  • Posts: 987
  • Registered: ‎06-03-2011
  • Location: United States of America
  • Views: 14800
  • Message 3 of 4

Re: SoS Girl : T420 XP Windows

2011-06-16, 19:03 PM

You could try Windows XP Professional x64 Edition; however, it doesn't work with lots of hardware. Normal Win XP is 32-bit and is limited to less than 4GB of RAM. You may want to consider going back to Windows 7 (Pro or better) and using Windows XP mode. For some people, XP mode will do everything they need. 

X1 Carbon 3rd Gen Type 20BT i7-5500U, 2560x1440 (non-touch), Win 10 Pro, 8GB RAM, 512 SSD, Intel 7625 WiFi, BT 4.0 | ThinkVision P24q-10 monitor

When asking for help, post your question in the forum. Remember to include your system type, model number, and OS. Do not post your serial number.

Did someone help you today? Thank them with a Kudo!

If you find a post helpful and it answers your question, please mark it as an "Accepted Solution"! This will help others with the same question in the future.

315 Posts



577 Signins

3826 Page Views

  • Posts: 315
  • Registered: ‎02-21-2008
  • Location: Singapore
  • Views: 3826
  • Message 4 of 4

Re: SoS Girl : T420 XP Windows

2011-06-17, 7:10 AM

As mentioned by others, the window operating system comes in 32 and 64 bit version. Most 32 bit versions can only address up to 3GB of memory while 64bit version would be higher limit.


When you see 3.86++ GB, the 0.86GB is 'shared' by your graphic card so you may not be able to use more than 3GB.


Why would you downgrade in the first place? in Window 7 64 bit, you can run the programs in XP mode when you right click on the program icon->Properties->Compatibility tab and choose XP mode IF that is available. XP was officially discontinued so I guess the latest Window 7 may not have this option.


If you need the memory, the ONLY stable and viable software I had used in the past is SuperSpeed RamsDiskPlus and cache etc. However, the software is useful only for ramdisk and some speedboost using the underutilized Ram

Forum Home

Community Guidelines

Please review our Guidelines before posting.

Learn More

Check out current deals!

Go Shop





No, I don’t want to share ideas Yes, I agree to these terms