You need a working BIOS to Flash the BIOS but if this is a Desktop M'Board you may be able to get a replacement BIOS Chip from a company like BIOS Central. I do this with Server Boards so that there is no chance of any issues arising when it's necessary to Flash the BIOS. It's far cheaper to replace the CHIP than to run the risk of getting the wrong BIOS Update.
remember to remove the space from between bioscentral and the .com for a working link.
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