I7 with Mainboard?

Some cpus will overclock, and some won't. It's never guaranteed. You need a good power supply with extra amps on the 12v rail, good ram, and a knowledge of bios settings. First item is find the cmos jumper on the motherboard. If the overclock fails, some boards won't post. You can reset the bios settings to default if this happens. With the system off, just move the cmos jumper over one position, keeping two of the three pins covered with the power supply unplugged. Then after one minute, move the jumper back to it's original position. You will also have to monitor cpu temps with a program such as coretemp, a free download. You don't want the temps to go above 80c; if it does, you need to reduce the cpu speed or get a better heatsink. I go for a 20-33% overclock.

can i just setup the FSB like on 775 model CPU's, cus some people told me the i7 needs some different overclocktechniques, my old intel core duo runs from 2,13 ghz now on 3,6 ghz.

rest specs for new pc with the i7:
8GB DDR3-1600mhz
1x Nvidia 460 GTX
650 W PSU

and an Scythe Katana 3 cooler

I'm not familiar with your board; start by setting the cpu fsb and to manual, and with a 25% overclock. For example, if your default cpu fsb is 133, change it to 167 and see if the ram fsb changes automatically with it. On many boards, the default memory fsb is only 1066, so overclocking the cpu is easy.

could you maybe check it , i'm not so good with maibaords, just knowing mayn about intel cor eduos and nvidia graphics

I don't see your model listed. There are two or three models of p7p55D, but no M models. Perhaps your system is oem, made by dell, packard bell, or hp.