P35-DS4 wont update to F13,F14 bios after on board ethernet is damaged

[stekosto]

I have this motherboard P35-DS4 updated with the latest bios and i have been experiencing  disconnects  on onboard Ethernet   from time to time.
Suddenly one day the system could not boot up.(freeze in bios, hdmi pool...)
I cleared up the cmos, put the battery out but no luck.
Then i started downgrading the bios one version at a time from f14 to f13 and then to f12.
At F12 bios system boots normally.It seems that ignore the defunct Ethernet circuit.
This of course prevents me to access a variety of s775 socket processors since many of them are supported only by the latest bios.
Any ideas how to resolve this issue and update the motherboard with the latest bios? (F14)

Thanks

[Dark Mantis]

In future if you update the BIOS make sure that you do it via QFlash and always make sure that the box marked keep CMOS data is cleared so that it refreshes the data pool as it goes. Try this next:

Remove the power cable from the mains supply and then press the power switch on the case for a few seconds just to drain any residual energy in the PSU capacitors.

Once done remove the motherboard battery for at least one hour before replacing it.
 
Next plug back into the mains supply and boot.
 
You will now need to enter the BIOS by pressing DEL and load Optimised BIOS Defaults.

Make any other changes to the BIOS settings to suit your self like disabling the floppy drive, disabling the full screen logo and making the HDD the primary boot device and then press F10 to save and exit.

[stekosto]

Hi, thank you for your interesting.
I have forgotten to say that the ethernet on board circuit is not working since then.

Now i upgraded system to the latest bios (F14) and keeps restarting when the enumeration of the system compontents occures.
By the way, if i install a cpu that is not supported by the currebt bios according to gigabyte's cpu list for this motherboard,  it is 100% proven that system won't recognize the cpu and won't boot?

Thanks

[Dark Mantis]

You will need to fit a supported CPU first so that you can get the system running and then update the BIOS to a version that does support the propcessor you have. No other way to do it and you can't cheat!