Frank Mehnert <[EMAIL PROTECTED]> writes: > On Thursday 01 February 2007, Heike C. Zimmerer wrote: >> Achim Hasenmueller <[EMAIL PROTECTED]> writes: >> > Looking at your VBox.log, it seems as if your CPU does not support >> > CMPXCHG8B. Wonder why Windows refuses to install without it. Maybe it >> > doesn't fully recognize the CPU and thinks it's Intel which has to have >> > the feature? >> >> Not sure if they are required. Looking into it further, I've stumbled >> across this bookmark: >> >> From http://radagast.bglug.ca/epia/epia_howto/x1099.html : >> >> The identification issue is that the C3 is identifying itself as >> 686. According to the Intel IA32 documentation, this is correct: C3 >> does not implement conditional moves*, and do not pretend to >> implement conditional moves. The Intel documentation states that >> you should check before doing conditional moves, and that cmov >> implementation in the processor is optional. > > I'm a bit confused about that HOWTO since CMOV has nothing todo with > CMPXCHG8B. And your CPUID states that the host _has_ CMOV.
Indeed. I took it for granted that they belong to the same capability group. > It is also possible that the installer detects VIA CPUs and expects some > other feature is not emulated by the VM, for example look at the CPUID > extended attributes at index 0x80000005 and 0x80000006. As I said, I'm not at all fluent at x86 assembly language. But after having a look at the CPUID spec and then into the VirtualBox log, it seems to me that the VIA CPU announces (at 8000_0000_eax) Fn8000_0004 as its highest available extended CPUID function number, whereas the guest receives Fn8000_0006 in this place (plus there's some content in there). Could that be the reason why the XP installer seems to assume a CPU type which is different from what it is running on? Thanks, Heike _______________________________________________ vbox-users mailing list [email protected] http://vbox.innotek.de/mailman/listinfo/vbox-users
