yben, the Dell Inspiron 580 Service Manual Dell™ Inspiron™ 580 Service Manual says that to reset the current CMOS settings:
Locate the 3-pin CMOS reset jumper on the system board.
Remove the jumper plug from the CMOS reset jumper pins 2 and 3.
Place the jumper plug on the CMOS reset jumper pins 1 and 2 and wait for approximately five seconds.
Remove the jumper plug and replace it on the CMOS reset jumper pins 2 and 3.
So give it a try. Once in the BIOS you should select safe boot options or similar choice and see if that works. If it does not you will have to flash the BIOS. Check [http://www.dell.com/support/home/us/en/19/product-support/product/inspiron-580/drivers|on here] for the software. Hope this helps, good luck.