Core synchronization. Is it possible?

Nope their is nothing in the bios for what you are asking. In fact there is no way to do that at all. For a program to utilize all your cores it has to be written to do so.

Darn, I thought it might cut down on overusing a single core. My AMD Phenom ll 925, tends to occupy Core 3 more than the rest while gaming.

It makes no difference to the CPU which core or how much a core is used your processor will most likely outlive its usefulness.

If you really want to force a game to not run on a certain core you could open task manager and right click on the game process and then goto set process affinity. There's no reason to do this, but I wanted to throw it out there that such an option exists.

I would not mess with those settings this could potentially throw your system into a tight loop situation not a huge deal a reboot will fix it, but there is no point to do this.