Thanks for quick reply
yes done everything as described format dos32 machine turned off green light on motherboard on, bios renamed with app to Z77ST.CAP, i have tried different usb sticks no luck , also tried unplugging sata devices no luck usb is in the correct slot as it is clearly marked pressed the bios button untill it starts flashing it reads the usb stick for about 5 seconds the blue light on button stays on and thats it. the bios downloaded from asus is ok because when i try to update in ezflash its reads off the same memory stick and updates ok, is my flash back faulty or am i doing something wrong. My board is the Sabertooth z77, theirs a number on the box MG1266U-C. I am using a intel i7 2600k not over clocked, 8MB of mushkin memory 1600 2x4, I am now at latest bios 1616 flash back still not working and it didn't work in previous bios, Thanks if you can help