Windows 8.1 upgrade and download link..

Windows 8.1 gives you the familiar desktop with its taskbar and Start button, plus
a beautiful new Start screen that you can customize with your favorite apps, people, and sites so that
everything you love is just a tap or click away.You also get built-in cloud storage for anytime, 
anywhere access to your photos and files, beautiful full-screen browsing with Internet Explorer 11, 
plus an exclusive collection of built-in apps like Photos and Mail, 
with many more apps available from the Windows Store. 
And that’s only the beginning
.Windows 8 system requirements

Windows 8.1

If you want to run Windows 8.1 on your PC, here's what it takes:

• Processor: 1 gigahertz (GHz) or faster with support for PAE, NX, and SSE2 
• RAM: 1 gigabyte (GB) (32-bit) or 2 GB (64-bit)
• Hard disk space: 16 GB (32-bit) or 20 GB (64-bit)
• Graphics card: Microsoft DirectX 9 graphics device with WDDM driver
  

  
  

  
  

Additional requirements to use certain features:

• To use touch, you need a tablet or a monitor that supports multitouch 
• To access the Windows Store and to download, run, and snap apps,
   you need an active Internet connection and a screen resolution of at least 1024 x 768
• Microsoft account required for some features
• Internet access (ISP fees might apply)
• Secure boot requires firmware that supports UEFI v2.3.1
   Errata B and has the Microsoft Windows Certification Authority in the UEFI signature database
• Some games and programs might require a graphics card 
  compatible with DirectX 10 or higher for optimal performance
• Watching DVDs requires separate playback software 
• Windows Media Center license sold separately 
• BitLocker To Go requires a USB flash drive (Windows 8.1 Pro only)
• BitLocker requires either Trusted Platform Module (TPM) 1.2 or 
  a USB flash drive (Windows 8.1 Pro only)
• Client Hyper-V requires a 64-bit system with second level address translation (SLAT)
   capabilities and additional 2 GB of RAM (Windows 8.1 Pro only)
• A TV tuner is required to play and record live TV in
   Windows Media Center (Windows 8.1 Pro Pack and Windows 8.1 Media Center Pack only)
• Miracast requires a display adapter which supports 
  Windows Display Driver Model (WDDM) 1.3, 
  and a Wi-Fi adapter that supports Wi-Fi Direct
• Wi-Fi Direct Printing requires a Wi-Fi adapter that supports 
  Wi-Fi Direct and a device that supports Wi-Fi Direct Printing
• Free internet TV content varies by geography, some content might require
   additional fees (Windows 8.1 Pro Pack and Windows 8.1 Media Center Pack only)
• To install a 64-bit OS on a 64-bit PC, your processor needs to support
   CMPXCHG16b, PrefetchW, and LAHF/SAHF
• InstantGo works only with computers designed for Connected Standby

If your PC is currently running Windows 7 or Windows 8 you can check to 
see if it meets the requirements by running the upgrade assistant.

Windows 8

If you want to run Windows 8 on your PC, here's what it takes:

• Processor: 1 gigahertz (GHz) or faster with support for PAE, NX, and SSE2 
• RAM: 1 gigabyte (GB) (32-bit) or 2 GB (64-bit)
• Hard disk space: 16 GB (32-bit) or 20 GB (64-bit)
• Graphics card: Microsoft DirectX 9 graphics device with WDDM driver

Additional requirements to use certain features:

• To use touch, you need a tablet or a monitor that supports multitouch 
• To access the Windows Store and to download and run apps, 
  you need an active Internet connection and a screen resolution of at least 1024 x 768
• To snap apps, you need a screen resolution of at least 1366 x 768
• Internet access (ISP fees might apply)
• Secure boot requires firmware that supports UEFI v2.3.1 Errata B and has
   the Microsoft Windows Certification Authority in the UEFI signature database
• Some games and programs might require a graphics card compatible with 
  DirectX 10 or higher for optimal performance
• Microsoft account required for some features
• Watching DVDs requires separate playback software 
• Windows Media Center license sold separately 
• BitLocker To Go requires a USB flash drive (Windows 8 Pro only)
• BitLocker requires either Trusted Platform Module (TPM) 1.2 or
   a USB flash drive (Windows 8 Pro only)
• Client Hyper-V requires a 64-bit system with second level address translation (SLAT) 
  capabilities and additional 2 GB of RAM (Windows 8 Pro only)
• A TV tuner is required to play and record live TV in Windows Media Center
   ( Windows 8 Pro Pack and Windows 8 Media Center Pack only)
• Free Internet TV content varies by geography, some content might require additional fees 
  (Windows 8 Pro Pack and Windows 8 Media Center Pack only)
  
  Upgrade                                           Download