Poweredge 4600 do not boot after update BIOS

Hello everybody!

The unexpected happened. There Server Poweredge 4600. I decided to update the BIOS (took away www.dell.com/.../DriversDetails). Downloaded PE4600-BIOS-WIN-A13.exe, I clicked Install, came after a reboot Black Screen, on which was written "bios update attempt failed". After the brief appearance of this message, the server is rebooted, and now nothing is happening - there is a black screen, the fans are spinning (at full speed, after about 1 minute after the revolutions subside to normal - I think something works ... I hope on this). What should I do? Good server, worked until the present times, I do not want to replace systemboard.
If it is important, it is not long before that, about a week of events was revealed failure usb-ports. This was the reason for the update bios.