cpu i5 turbo boots

[du5k0]

Hello,
I have intel i5-2410M. When i use prime95 for CPU stress I see that max clock frequency is 2.7Ghz.
But in intel specification says that max boost frequency is 2.9Ghz.
Is limited in bios, or ...

Thanks in advance

 

[rgd1101]

http/www.cpu-world.com/CPUs/Core_i5/Intel-Core%20i5%20Mobile%20I5-2410M.html
2.9 only when 1 core is active.
2.7 for 2 cores