If you have an older AMD CPU based system and you attempt to install or upgrade to Windows 8.1 you will see a message like:
You can’t install Windows 8.1 because your processor doesn’t support CompareExchange128.
This is true but there are three important points to note:
- 32BIT Windows 8.1 will install / upgrade
- of course you can NOT upgrade 64Bit Windows 7 or 8 to 32Bit Windows 8.1 but you could perform a fresh install
- 32Bit OR 64 Bit Windows 8.0 WILL install / upgrade
- APPARENTLY 64Bit Server 2012 R2 WILL install
- I have not tested this
The limitation on 64 bit Windows 8.1 applies to AMD Athlon 64 / Opteron 1, 2 or 8 series CPU on Socket 939 754 etc.
That being said I a THRILLED to get an amazing Alienware MJ-12 8550A running Windows 8.1 with NO extra drivers or utilities. After the initial boot, I did a Windows update which caught the new drivers for the nVidia Go1400 card and a few other items. Even the media buttons on the front of the ‘laptop’ plug and played. It is running perfectly well. AMAZING for a machine from 2006!