While trying to upgrade the bios from F4 to F9 using @bios, we hit trouble when the progress meter stopped halfway and we received a message saying that the bios failed to load successfully. We figured that we had better try updating the bios using a floppy and good old DOS based award bios utility. We weren't too worried because, hey, we had a dual bios motherboard that would automaticaly boot from the backup bios if there were any problems with the main bios right? Wrong! Turns out that there was enough bios loaded into the main chip to kick off on the main chip but not finish loading. The systen would POST ok (we could see it loading F9) and detect all drives but then freeze. We expected to be able to boot to DOS but could not get that far.
After some research, we came accross this post which was great help but it related to a different chip to ours. The GA-K8NXP series boards use SST-49LF004A bios chips. These are commonly used by other vendors also. Using the tips from tgun's post, we got hold of the data sheet and started playing. We worked out that the system does not actually boot from the backup bios but rather uses the backup to reprogram the main chip if there is a problem. Our intention was to try and disable the main bios, thus forcing the backup to be copied over. Remember the backup still had version F4 loaded.
After some trial and error we discovered a process that worked for us. Hopefully it will be of some help to you also. Basically we needed to disable the main bios just long enough for the system to revert to the backup but not so long as to prevent the system from copying the backup to the main again. Here we go...
OK, a couple of pointers.
Hope this is of some help to those in a similar situation. Final tip... Don't use @bios. It sucks.
After some research, we came accross this post which was great help but it related to a different chip to ours. The GA-K8NXP series boards use SST-49LF004A bios chips. These are commonly used by other vendors also. Using the tips from tgun's post, we got hold of the data sheet and started playing. We worked out that the system does not actually boot from the backup bios but rather uses the backup to reprogram the main chip if there is a problem. Our intention was to try and disable the main bios, thus forcing the backup to be copied over. Remember the backup still had version F4 loaded.
After some trial and error we discovered a process that worked for us. Hopefully it will be of some help to you also. Basically we needed to disable the main bios just long enough for the system to revert to the backup but not so long as to prevent the system from copying the backup to the main again. Here we go...
- Remove the mobo from the case so that you can work on it easily. Remove the sensitive items such as RAM and CPU and any cards also.
- With the mobo sitting on some non conductive surface (a mobo box is handy here), solder two insulated wires onto the pins 31 (CLK) and 24 (OE). See the image below and check the data sheet for the physical locations of these pins. Be very careful not to short any of the other pins together and make sure you have your anti static strap on.
- Now install a video card, monitor, some RAM and a CPU (with a fan of course).
- Connect a power supply and turn it on.
- Get ready to hold the exposed ends of two soldered wires onto a ground point. You can use any of the metal casings around the mobo connection ports or the grounding points where the mobo mounting screws are installed. Don't ground them yet!
- Fire up the mobo by shorting the power switch pins temporarily (check your manual if you are not sure which ones they are). Normally you should see the monitor status LED go from standby to active, back to standby briefly and then active again. After the second active signal (green led usually) the monitor will start scrolling the normal POST messages until it freezes at some point because of the dead bios. What we had to do was to short the two bios pins (Clock and Output/Read Enable) just as the monitor went from the first active signal to standby and then hold them grounded until a few seconds after the second active monitor signal came on. At that point we stopped shorting the pins and the backup bios program appeared stating that it was restoring the main bios from the backup chip. Once it was done we just rebooted it and the bios was fixed!
OK, a couple of pointers.
- You know it has booted from the backup if you see the previous version number (in our case F4) come up on the monitor as it boots. This is maybe the second thing you see. Once you see that, remove the short from the bios pins and let it do its stuff. If you see the number of the updated bios (in our case F9), you need to start again because it is trying to boot from the faulty main bios chip.
- If you hold the short on for too long, you may see the bios backup program appear with a message that says "Write error on main bios, press any key to continue". You must only disable it long enough to detect the fault and switch to the backup, after that, the main must be enabled before it can be reprogrammed. Try again.
- If you ground the pins too early, the monitor may not fire up at all. You are shorting out the clock pulses after all. I guess the system needs to see those pulses initially before even begining to boot.
- Use a fine tipped soldering iron!
- If it does not work grounding both pins, try just grounding the CLK (Pin31) only.
- Playing with a mobo at this level is risky. The risk is that you may kill the mobo...but then again it's no good without a bios anyway right!
Hope this is of some help to those in a similar situation. Final tip... Don't use @bios. It sucks.
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