|Sometimes the required flash utility version changes for bios updates for the same mboard model.|
If the previous bios version bin or whatever file you saved requires that you use a different flash utility version, that could be where your problem trying to restore the previous bios version lies.
There is a big difference between the bios not detecting (a) drive(s) , and detecting all drives but not detecting a bootable drive.
NOTE that, if you have more than one hard drive connected, if your problem was the bios was not booting an operating system from the correct drive with default bios settings, sometimes you need to CHANGE a setting in the bios.
When you have more than one hard drive connected, at least one has an operating system on it, and at least one does not, default bios settings may not be booting from a drive with an operating system on it.
If the first hard drive the bios detects by default, or is custom set to detect, is NOT found to be bootable, the bios will NOT try to boot from anything else in the Boot Order or similar list, and/or any other hard drive it detects.
In most modern bioses, when you have more than one hard drive, there is a list of hard drives in the bios, often near the Boot Order or similar setting. The drives are usually listed by their model. The drive you want to boot an operating system from must be listed first in that list - Save bios settings
Or - for the drive that has an operating system, you can change which data header it is connected to if it's SATA, or that or change the jumper setting if it's IDE, so that the bios does detect it first by default, according to where and the way it is connected. If you have both a SATA and an IDE hard drive, some bioses detect the IDE drive first by default, some detect the SATA drive first by default.
Obviously, if you have the list of hard drives in the bios, it's often much easier to change the drive order in that.
I'm assuming that if you have IDE drives that you HAVE NOT changed the jumper settings on the back of the drives. If you have, you WILL have problems detecting drives if you didn't set those the right way.
- you don't mix Cable Select and Master / Slave settings for two drives on the same data cable
- some IDE hard drives - e.g. many Western Digital models - have two ways they can be set to Master - one for when the drive is by itself on a data cable, the other for when there is another drive set to Slave on the same data - that MUST be correct for the situation
Other than that....
Your problems regarding detecting drives are many times more likely to be caused by
- (a) data cable connection problem(s)
It is common to un-intentionally damage IDE data cables, especially while removing them - the 80 wire ones are more likely to be damaged. What usually happens is the cable is ripped at either edge and the wires there are either damaged or severed, often right at a connector or under it's cable clamp there, where it's hard to see - if a wire is severed but it's ends are touching, the connection is intermittent, rather than being reliable.
Another common thing is for the data cable to be separated from the connector contacts a bit after you have removed a cable - there should be no gap between the data cable and the connector - if there is press the cable against the connector to eliminate the gap.
80 wire data cables are also easily damaged at either edge if the cable is sharply creased at a fold in the cable.
Try another data cable if in doubt.
80 wire data cables must have the proper end connector connected to the mboard IDE header - usually that's blue, but in any case it's the one farther from the middle connector on a 3 connector data cable.
Check your SATA data cables. The connector on each end should "latch" into the socket on the drive and on the mboard, or on the drive controller card - it should not move when you merely brush your hand against it near the socket - if it does, mere vibration can cause a poor connection of it - use another SATA data cable that does "latch", or tape the connector in place.
(There is a slight projection or bump on one side of the outside of the connector that "latches" it into the socket - it's easily broken off or damaged)
The same thing applies for the SATA power connection.
- less likely - sometimes you need to change a default bios setting that specifies how long the bios takes to detect drives - and use a longer time