Most of the folks will recommend flashing the BIOS only if there is a specific need, and on the Gigabyte boards, using the QFlash appl after downloading the BIOS file on a floppy or USB flash drive. Few will recommend using the Windows @BIOS because of problems and risk of updating with that utility.
Are you able to get to your BIOS splash screen before the bootloop occurs? If so, you can click on key without getting into the BIOS itself and update the BIOS from a flash drive. Or if you backed up the original BIOS file before using @BIOS, you might be able to reload that.
4-2-1 Updating the BIOS with the Q-Flash Utility
A. Before You Begin:
From GIGABYTE's website, download the latest compressed BIOS update file that matches your motherboard model.
Extract the file and save the new BIOS file (e.g. p35ds3l.f1) to your floppy disk, USB flash drive, or hard drive. Note: The USB flash drive or hard drive must use FAT32/16/12 file system.
Restart the system. During the POST, press the key to enter Q-Flash. Note: You can access Q-Flash by either pressing the key during the POST or pressing the key in BIOS Setup. However, if the BIOS update file is saved to a hard drive in RAID/AHCI mode or a hard
drive attached to an independent IDE/SATA controller, use the key during the POST to access Q-Flash.
Because BIOS flashing is potentially risky, please do it with caution. Inadequate BIOS flashing
may result in system malfunction.
If that's not successful, you should follow the instructions on page 29, to reset the CMOS. Requires turning off and unplugging your computer, then shorting out the Clr CMOS pins as instructed.
CLR_CMOS (Clearing CMOS Jumper)
Use this jumper to clear the CMOS values (e.g. date information and BIOS configurations) and reset the CMOS values to factory defaults. To clear the CMOS values, place a jumper cap on the two pins to temporarily short the two pins or use a metal object like a screwdriver to touch the two
pins for a few seconds.
That should reset it back to the initial BIOS version, to at least get you going.