Thanks @HpBiosGuy for your post
I've tried several flash drives, fat16 and fat32. Only one file in root (hash file checked in flash drive).
The BIOS file "CUP_716.ROM" from sp58264.exe (4MB File) works fine in other hp pro 3300 mt. I dont use "PO2_806.ROM" from sp60638.exe because is a 8 MB BIOS
The motherboard have some jumpers CLR_CMOS, RST_CMOS, BB_RECRY (caped, without pins) OST_RST and OST_RECRY
I don't find any documentation.
This is the procedure extracted from another HP Manual
We dont have Carepak, and no guarantee
I need to recover this PC. Really.
Boot Block Emergency Recovery Mode permits system recovery in the unlikely event of a ROM flash
failure. For example, if a power failure were to occur during a BIOS upgrade, the ROM flash would be
incomplete. This would render the system BIOS unusable. The Boot Block is a flash-protected section
of the ROM that contains code that checks for a valid system BIOS image when the system is turned
on.
If the system BIOS image is valid, the system starts normally.
If the system BIOS image is not valid, a failsafe Boot Block BIOS provides enough support to search
removable media for BIOS image files. If an appropriate BIOS image file is found, it is automatically
flashed into the ROM.
When an invalid system BIOS image is detected, the system power LED will blink red 8 times, one blink
every second. Simultaneously, the speaker will beep 8 times. If the portion of the system ROM containing
the video option ROM image is not corrupt, Boot Block Emergency Recovery Mode will be displayed
on the screen.
To recover the system after it enters Boot Block Emergency Recovery Mode, complete the following
steps:
1.
Turn off the power.
2.
Insert a CD or USB flash device containing the desired BIOS image file in the root directory.
NOTE:
3.
Turn on the computer.
If no appropriate BIOS image is found, you will be prompted to insert media containing a BIOS
image file.
If the system successfully reprograms the ROM, the system will automatically power off.
4.
Remove the removable media used to upgrade the BIOS.
5.
Turn the power on to restart the computer