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Old March 11th 04, 02:55 AM
kony
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On Thu, 11 Mar 2004 00:40:47 GMT, Mark M
wrote:

I use a partition copier which boots off a floppy disk before any
other OS is launched.

If I copy a partition from one hard drive to another, then is there
any risk of data corruption if the BIOS has been changed to
aggressively speed up the memory settings?


Yes, a relatively high risk.


For example the BIOS might set the memory to CAS=2 rather than
CAS=3. Or other memory timing intervals might also be set to be
shorter than is normal.


Yes, that'll _potentially_ cause errors, corrupt the data.

I am thinking that maybe the IDE cable and drive controllers handle
data fairly independently of the memory on the motherboard. So
maybe data just flows up and down the IDE cable and maybe the
motherboard is not involved except for sync pulses.


It's involved. Hint: Consider what "DMA" stands for.


There are three scenarios I am thinking about:

(1) Copying a partition from one hard drive on one IDE cable to
another hard drive on a different IDE cable.

(2) Copying a partition from one hard drive to another which is on
the same IDE cable.

(3) Copying one partition to another on the same hard drive.

How much effect would "over-set" memory have on these situations?


It has the same effect on all, that "IF" the memory is set incorrectly or
defective (or motherboard issue, etc), that if errors occur all of the
above scenarios are a risk.

Do the answers to any of the above three scenarios change if the
copying of large amounts of data files is done from within WinXP?
Personally, I would guess that it is more likely that motherboard
memory comes into play if Windows is involved.


It's the same risk, but with more memory used there's even a greater
chance of errors, not necessarily all occuring in the data transfer but
ALSO the OS, so both the backup AND the OS would potentially be using
corrupt data... never boot to the OS if there's any question of memory
instability, else be prepared and expecting to reinstall everything unless
you can restore or recreate every file written during that interval of
operation.