The bios should say 3.4 as the 'boost' dynamically increases the cpu multiplier when needed. It's a separate setting and will only increase the cpu speed when required. Read the details on this site to understand. How Intel Turbo Boost Works [Technology Explained]
"What is Intel® Turbo Boost? This technology looks at how the processor is running, where it is using all the cores and it TDP (Thermal Design Power) if it hasn’t reached these limits it will increase the clock speed up to reach a faster speed to stay within the TDP. You can install this software and it will show you when your processor clocks up speed in Intel Turbo Boost http://downloadcenter.intel.com/Detail_Desc.aspx?agr=Y&
.... Most of the time your system won’t be using Intel Turbo Boost but when you need increased performance it is nice to have it right there waiting for you to use. For more information on the Intel Turbo Boost Technology you can check this out http://www.intel.com/support/processors/sb/CS-029908.ht...(turbo+boost)."
If still uncertain use the software mentioned in the quote and it should clarify the situation.