Advanced CPU settings blocked on BIOS :(

Hi everyone I have a motherboard ASUS P5G41-M LX2/GB and I recently bought a nice CPU cooler (Vortex Plus/Cooler Master) with the only intention to gain some extra Mhz into my CPU but when I try to modify the Advanced CPU settings on the BIOS they are kind of blocked and i can't change any setting , I tried everything on the manual, also tried to use some OC software such as SetFsb but my PLL is not listed, so is there any way to unlock those settings?

Here are my Pc specifications;
Intel Pentium E6500 (Wolfdale) Pentium(R) Dual-Core CPU @ 2.93GHz
L2 cache 2048 KBytes, 8-way set associative, 64-byte line size
Memory Size DDR2 3072 MBytes
Channels Dual, (Symmetric) Memory Frequency 333.6 MHz (4:5)
NVIDIA GeForce 8400GS Memory size 512 MB

So if anyone can help me I'll be in debt for the rest of mi actual PC life

That sucks that your motherboard is locked up tighter than fort knox, but you do still have an option. Since you are using an Nvidia card, you can try using Nvidia System Tools. Just go to their website and search for system tools. It will allow you in the performance section to change the FSB, Memory timings, multiplier (sometimes), cpu voltage (sometimes), as well as overclock your video card. That is about your only option. Those Wolfdales are some wicked overclockers. With a good board you could/should be able to see 4Ghz or more (on water).
-Greg

Looking within the Manual...

...manual for that motherboard, we see this on Page #33 of Asus Mother Manual E5070_P5G41-M LX2 Series.pdf.

2.4.1 CPU Configuration
The items in this menu show the CPU-related information that the BIOS automatically detects. Ratio CMOS Setting [Auto]
Sets the ration between CPU core clock and the FSB frequency. Configuration option: [Auto]

That would appear the ONLY option that might have been adjustable for any minor overclocking and if AUTO is the only setting then that board is by no means meant to be an overclockable product.

I can understand why things might be that way since Intel binned the P45 chipsets and those that fell lowest in the binning process became P43 and apparently on down to P41 type chipsets. I would not expect the P41 chipset to have handled an overclock very well at all.