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AT-x acceleration suddenly disabled??

I've been running a virtual machine (Oracle VirtualBox) on my Sp3 every since I got it, with no problems. Today, I start seeing this:

VT-x/AMD-V hardware acceleration is not available on your system. Your 64-bit guest will fail to detect a 64-bit CPU and will not be able to boot.

Not having much luck troubleshooting this from the Oracle side of the fence - is there any way to check that hardware acceleration is indeed enabled on my SP3??



Staff member
Weird....I ran the Intel Processor Identification Utility and I of my VT-X with Extended Tables are working....
Turns out I had installed Visual Studio 2013 yesterday and it kindly assumed I wanted Hyper-V enabled, which is why I'm getting this message now from VirtualBox. Disabled Hyper-V and problem goes away :)


Well-Known Member
In cases like you described, I always ask my clients what has transpired on your computer from the time it was last working correctly until it quit working correctly. Most of the time it was something the user did that created the problem.