I am trying to install windows 8.1 or 10 preview with processor (Intel E8400 core2duo 3.0ghz) but an issue of compare exchange 128 exist.

I tried by downgrading with my old processor back to (Intel E4600 core2duo 2.4ghz) which i have in spare , it works.

Why it isn't working with E8400 processor which has much better specification than E4600.

:(

Hello KRISHNA NAIR,

Do you receive error message You cant install Windows 8,1 because your processor doesnt support CompareExchange 128?

This is the hardware devices compatibility issue, to receive better support, it is recommended to contact the manufacturer.

Best regards,
Fangzhou CHEN

I would recommend setting your BIOS to defaults after installation of the new processor. My research indicates that CMPXCHG16B is supported on the Intel Core 2 Duo E8400. Your BIOS may contain the ability to enable or disable this function and it may need to be enabled explicitly. You can also determine if it is visible with CoreInfo, the item is CX16.

Brandon
Windows Outreach Team- IT Pro
Windows for IT Pros on TechNet