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During boot of VMware ESXi 3.5 install CD, I got the message

Unsupported BIOS setting (CPUID is limited). Disable 'limit CPUID value' or 'Support legacy/NT4 OS' in BIOS

After googling, this is a common problem and after following the fix at , everything worked fine.

My question is, what does this mean for me? Do I have a crippled install of VMware because I've effectively bypassed this check that obviously it really cares about? (pink screen of death). What features, if any, am I losing out on?

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It means you're using a massively out of date hypervisor for a start. – Chopper3 Feb 17 '12 at 20:47
Have you considered following the instructions your software gave you (Disable 'limit CPUID value' or 'Support legacy/NT4 OS' in BIOS)? Then you don't have to worry about what it means :-) – voretaq7 Feb 17 '12 at 21:09
Voretaq: there isnt an option for that in my bios. I wanted to know what effect if any removing the check from vmware had – psynnott Feb 18 '12 at 12:06
up vote 3 down vote accepted

Having CPUID off is best. Older operating systems get confused by certain processors when querying them for information, and limiting the CPUID means the bios stops the OS getting confused about the capabilities of the CPU by limiting the amount of information returned. In such a case, you'd enable the setting, but it's unlikely to be required anymore (it's only for legacy systems).

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