Norm said:
[snippage of a lot of good stuff]
Thanks very much for the good advice and the links, Paul.
I ran into a problem with update of the BIOS of my Acer M1640. I was only
able to run the downloaded flash update program using my Vista U-64
partition. That seemed reasonable. I saved the old BIOS to a 1 MB file and
loaded a .221 file that looked OK. The flasher program identified the file
contents as the desired update BIOS. So I ran flash and watched the flash
process which was slow. The flasher ran verify and all the flash cells
showed green. I rebooted and hit DEL to run the BIOS program and checked
everything. Everything looked OK and the new BIOS version R01-C2 was
displayed. The RAID info was preserved. I saved one small change.
Now when I try to boot I am told there is a bad checksum and I am given two
choices, F2 use old values, which hangs on the RAID or F1 which lets me back
into the BIOS program. Now the BIOS setup program tells me the RAID setup is
forgotten. For the life of me, I cannot remember which three of four drives
I used.
Isn't this a kick in the pants? I can probably boot from a non-RAID drive.
And maybe after a few days I will figure out how to set up the three drive
RAID 0 storage array.
Comments?
PS Booting from three drive RAID 0 storage array is MUCH faster than a HDD.
Maybe a quad CPU upgrade would help.
Well, I don't know if I can interpret those symptoms or not.
The NVRAM can have a bad checksum. AFAIK, that's the contents of CMOS.
The CMOS is used to store motherboard settings.
If the BIOS had a checksum error, over the main code block, then
you probably wouldn't be getting any BIOS screen at all.
If you "Load Setup Defaults" in the BIOS, that will blow away the
CMOS contents and load a default set of values.
OK, now on to the RAID.
The SATA ports need to be set in some mode. This is used two ways:
1) At the BIOS level, the BIOS RAID module needs to know what is going
on. To read sectors from the RAID, for boot purposes, it has to
be in "RAID Mode". If the disks are in RAID Mode, the RAID module
needs to be enabled, so it knows how to read from the disks (take
interleaving into account).
2) The BIOS loads values into hardware, that when the Windows driver
sees them, the RAID driver loads. And does its thing.
OK, so what the BIOS is contributing, is an annotation that the
Southbridge is in a soft RAID mode.
The hard drives themselves, each drive has metadata at the end,
that declares there are one or more arrays stored on the disk.
The membership is recorded (maybe, by serial number). No matter
which port you connect the disks to, the BIOS notes the information
about role, and makes sure the disks are used appropriately.
Now, if you flash the BIOS, mess up the NVRAM, then what is lost ?
The RAID mode setting is lost. Maybe the computer is in AHCI or
IDE mode. The three disks are now handled separately, and perhaps
the information is then not suitable for booting (or, anything else).
The metadata should still be on the drives. So nothing should be
lost from that perspective. It's still a set of RAID disks.
You have to get the motherboard back in RAID mode.
I wish there was an accurate way to record CMOS settings, but
there just isn't a guaranteed way to do it. Various brands and models,
may have come up with their own solution. One motherboard, for
example, had the ability to "store profiles". And a profile
could put back settings. The problem with this is, when you change
BIOS versions, the BIOS is not clever enough to rework the datafill
of the profile, such that the BIOS settings make sense with the new
BIOS. In other words, the profiles are only of use to a particular
BIOS version, and there is no guarantee the byte patterns can be reused.
If the info was stored in plain English, like "SATA 5 = AHCI mode",
then the new BIOS could load the appropriate value to make that happen.
I recommend going into the BIOS, and doing your best to put the
ports in question, back in RAID mode. If the board has multiple
storage chips, make sure your cabling and chip choice are still
consistent with what you're doing.
I'm hoping your checksum error, has nothing to do with the
BIOS flash itself (main code is bad).
*******
When you flash a BIOS, sometimes the NVRAM no longer aligns with
definition of things in the new BIOS. You'd think if a developer
had half a clue, there'd be a wall poster over their desk that
says "don't screw with the definitions". Since they can and do
screw with the definitions, we're told as users that we should be
"clearing the CMOS", or, if the BIOS will come up at all, using
"Load Setup Defaults" to initialize the CMOS values. By doing that
after the BIOS flash, that allows the BIOS code to recognize that
the CMOS needs to be reloaded. That would include calculating a
new CMOS (NVRAM) checksum. The CMOS actually has two checksums,
one checksum over the majority of bytes, while the two BIOS passwords
have their own checksum. The CMOS is only 256 bytes of storage
in the Southbridge "CMOS Well", and not all of it is used. But
it's still important stuff, if it prevents the BIOS from
starting (or booting).
Some BIOS flasher packages, the .bat file includes an argument
to the flash tool, that tells the flash tool to reset the NVRAM.
In other cases, it's left to the user to clean up the mess on
their own.
If for some reason, the BIOS didn't start at all, you could
"clear the CMOS". But before you do that, remove all power.
A large number of desktop motherboards, have been designed
such that a certain diode on there, gets burned if you
clear CMOS with power present. Normally, this fact is
mentioned in the procedure for clearing CMOS (just not in
so many words - they tell you to turn off the power, but
don't tell you what the consequences are, of failing to turn
off the power).
Once you've reset the settings, using one of many methods,
now you have to go back into the BIOS, and put the
controllers back in their original modes. So the
Windows drivers will align with the hardware. On at
least one of my motherboards, there were two bad defaults,
and I can't count the number of times I've had to go in
and correct those. So any time the settings get reset on
that one, it's a teeth gritting experience for me (time
waster). For that one, the settings get reset, if
the BIOS "thinks" the computer crashed during its
last session (an Asus feature). So it's not like I'm
shorting the CMOS pins every day. It's a BIOS issue.
It's supposed to automatically recover the computer
from an overclock... even if it wasn't overclocked.
Paul