dont know if this actualy belongs here but here goes,
i bought an asus p5k motherboard with an intel core 2 duo, the probem was that i kept getting an error during system startup that my cpu is unkown and i need to update the bios to unleash the cpu power even after i installed the drivers from the cd.so i downloaded the latest bios from the website and used the asus bios updater included in the cd to update the bios and after the second part of the update i got an error in the 3rd part and then restarted the computer.
now nothing happens in the start and system keeps getting restarted.nothing shows in the monitor just restarting...
so i tried to reset the bios but unpluggin the cables and removing the bios battery for 1hour or so even putting it in reverse but nothing worked.
completely stucked over here, anyone can help please?

You've already learned the first lesson...never, ever use the ASUS Update utility. It used to work really well but for whatever reason it almost always results in a corrupted BIOS now.

Here are the steps from the manual to recover the BIOS:

1. Insert the USB flash disk that contains BIOS file to the USB port.
2. Turn on the system.
3. The utility will automatically check the devices for the BIOS file. When found, the utility reads the BIOS file and starts flashing the corrupted BIOS file.
4. Restart the system after the utility complets the updating process.

NOTE 1: The flash disk should be formatted as FAT or FAT32, NTFS is not supported. It should also bee smaller than 8GB.
NOTE 2: DO NOT shutdown or reset the system while updating the BIOS.

ok, extracted the ROM file into the formatted fat-16 flash drive and plugged it, then started the computer and still the same.
im afraid worse than that cause nothing appears on the screen not even the first screen which displays the graphic cards info,system restart in like every 2 seconds.no time to load anything.

Let's get deeper in the issue: take out the CMOS battery, copy the ROM file to a floppy disk, insert the battery back in its position and the floppy in the drive and start the pc. And let us know if it worked.

i dont have FDD drive on my pc , removed it long time ago.
is there any alternative to that? maybe usb flash drive?

I believe you have to make sure the file is named PK5.ROM. I know the instructions don't say this but give that a shot. If all else fails you can try it from the CD that came with the motherboard (just put it in the drive and turn the system on).

i renamed the file to both p5k and pk5 and used both usb and cd but still nothing, as i said the computer stays on for 2 seconds so no time to load anything i guess.
i already tried removing all the slots like hdd,dvd-rom,wireless and others to see if any cause this but not a diffrence.only thing remains is the power supply and im gona bring another one to test today.
though any other suggestions?

Well i used Asus update utility a short while ago without a problem. But you have to check the downloaded file first before you update.