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I have a Asus P5K SE motherboard and I recently changed the CPU from a Core 2 Quad to a Core 2 Duo. After the change a message displayed at the very beginning of the boot:

Unknown CPU detected, Bios update is required to unleash it's full power. The system will shutdown after 25 seconds.

I believe this indicated that I must perform a BIOS update. The problem is that I cannot boot. Not into windows, nor to CDROM or anything else. It is not even letting me to enter the BIOS setup.

How do I flash the BIOS without being able boot from anything?

Thread UPDATE: I was able to flash the latest BIOSs without changing the CPU using the integrated ASUS flash tool; after flashing the BIOS successfully and rebooting I got rid from the CPU message; instead I got this message. I removed all the USB devices, and the front USB wires, and placed the motherboard on a non metal surface but still have this USB message, any ideas?

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Unleash the Core 2 Quad back into the motherboard, unleash the BIOS update, unleash the Core 2 Duo. – May 31 '14 at 9:12
Have you tried entering the BOIS since flashing the new version? Are you sure the version you flashed was for your make /model of motherboard? Sounds like it may not have flashed properly – Jonny Wright May 31 '14 at 9:50
no i cant enter the BIOS after flashing , yes it was for that model and from asus site , i had watched a youtube tut and the flash tool graved me o error messages – Alexander May 31 '14 at 13:18

Answering this since it is an unswered question since may 2015 and hence will pop to the front page now and them.

  • Either revert to the old CPU and update from a fully working system,
  • or use the integrated ASUS flash tool
share|improve this answer
He already successfully updated, though. ;) – Daniel B Dec 10 '15 at 18:01
True. But it will get popping up and up until it receives an accepted answer. (andif the OP posts his or her answer and accept it then I will be glad). – Hennes Dec 10 '15 at 18:03

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