ex_bubblehead :
There are no "hidden" settings in BIOS. If you don't see a particular setting then it doesn't exist in the code. The only thing those so called tools do is corrupt a perfectly good BIOS and turn a motherboard into a brick.
This isn't quite true. Almost all motherboard firmware (BIOS/UEFI) is derived from one of only a handful of different firmware packages that are designed around compliance with a particular platform and chipset. Of this handful, only AMIBIOS (American Megatrends) and Insyde are in development.
Motherboard vendors and OEMs such as Asus, Gigabyte, Dell, HP, Acer, and Gateway licence the firmware package as a starting point and modify it from there. Some vendors enforce specific defaults by removing the ability to change some settings. This is often accomplished by disabling certain menus that would normally be accessible from within the system setup, thus preventing the user from overriding the defaults.
For example, the firmware must configure the DRAM with a particular voltage level and timings before bringing the DRAM out of initialization. Some vendors may prevent the user from mucking around with these values to enforce consistence for quality of service reasons, while other settings may be locked out because they are irrelevant to the platform (for example, settings for SATA or USB ports that aren't wired up).
Unlocking the menus that hold the relevant sections is quite simple and can be accomplished with a hex editor and knowledge of the firmware image structure. As a consequence though, it can enable a careless user to damage the product or render it unusable.
@OP: you should take a look for a flashing tool that is provided by your OEM and use that with the modified image. Flashing tools provided by the firmware chip provider are intended for developers, not users. I must caution you though that these custom firmware images are rarely done professionally and may cause problems and/or confusion.