Not only is it 100 MHz, you should not try adjusting it to Overclock a NON K CPU. Some do, ie raise it ro 103 MHz., But:
.. It's not worth it, in that 3 MHz x multiplier of 33 only eauals 100 Mhz, or a increase CPU of 3% - never notice it.
.. This is also used for PCI-e bus which is NOT very friendly to changes in the 100 MHz.
BCLK more or less ties all frequencies together like the USB ports. When the BCLK is raised above 105 the USB ports may no longer respond. Raise the BCLK even more and the USB ports can be permanently damaged. Simply stated if you want to overclock, you should get a "k" model like the 2500k or the 3570k.
BTW, good riddance to FSB. Moving to the PCH instead of Hub was so great for performance. Much better memory performance and having on-die PCIe controller is great. As is removing the southbridge chip.