Theree's no point in deactivating the graphic card in the device manager - it actually is not possible - all you can do is set it to Standard VGA mode which in turn is a no-go as well.
Please post the system info from the Lightroom help menu. Don't forget to black out your serial!
Here is the system info, sorry it took me so long to reply...
Lightroom version: CC 2015.3 [ 1052427 ]
Operating system: Windows 10
Application architecture: x64
System architecture: x64
Logical processor count: 2
Processor speed: 1.9 GHz
Built-in memory: 3003.1 MB
Real memory available to Lightroom: 3003.1 MB
Real memory used by Lightroom: 343.9 MB (11.4%)
Virtual memory used by Lightroom: 298.4 MB
Memory cache size: 86.4 MB
Maximum thread count used by Camera Raw: 2
Camera Raw SIMD optimization: SSE2
System DPI setting: 96 DPI
Desktop composition enabled: Yes
Displays: 1) 1366x768
Input types: Multitouch: No, Integrated touch: No, Integrated pen: No, External touch: No, External pen: No, Keyboard: No
Graphics Processor Info:
Check OpenGL support: Failed
GL_MAX_FRAGMENT_UNIFORM_COMPONENTS (actual = 128, minimum = 1024)
GL_MAX_TEXTURE_SIZE (actual = 1024, minimum = 2048)
Application folder: C:\Program Files\Adobe\Adobe Lightroom
Library Path: C:\Users\User\Pictures\Lightroom\Lightroom Catalog.lrcat
Settings Folder: C:\Users\User\AppData\Roaming\Adobe\Lightroom
1) Canon Tether Plugin
4) Leica Tether Plugin
5) Nikon Tether Plugin
Config.lua flags: None
Adapter #1: Vendor : 8086
Device : 2a42
Subsystem : 360b103c
Revision : 7
Video Memory : 64
Adapter #2: Vendor : 1414
Device : 8c
Subsystem : 0
Revision : 0
Video Memory : 0
AudioDeviceName: Speakers (Conexant High Definition SmartAudio 221)
GPUDevice: not available
I made sure my driver was up to date, and it is set at 3072, well above the "recommended" size...
The part where the type of your graphic card should be is empty/missing - can you tell us the type?
Your card/driver (OpenGL) seems not to be supported. Did you check your system compatibility for Win10 before upgrading? You have only 3GB of RAM, which IMHO is not really enough for a x64 system.