Strange hard disk behaviour

OK, so here's what I have,

1 40GB Fixed disk (2.5" IDE). Partitioned into 3 drives, 1GB for the
OS with a RAM EWF. The other two partitions are just standard 15GB
partitions.
When my terminal is first booted after cloning I have a few scripts
that fire up and update the terminal with our applications. Most of the
time this works fine, terminals boot, terminals get apps,
everything's fine. However about 1 in 20 terminals will fail, it
seems that the d: is unavailable, all the configuration files on d:
disappear (they definitely get put there correctly), also the system
event logs (from the OS) are missing all the detail from their first
boot. It's like d: has been formatted, but it's not by me.

This is a problem that I can build a kludge to get around it, but the
disks not being there is a real problem. Also I have 600 of these
suckers due to go into QA for scale testing next week, so I'm
expecting around 30 to fail, which is not good.

Has anyone come across anything that even slightly looks like this kind
of problem or has any suggestions on where to look to try and fix it?

Cheers for any help.
Rob

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