Help!!!

Some time ago my server [NetBSD 1.3.2] was brutally turned off by a
black out.
When I turned on again, I had to do an fsck, that told me about some
file system problem "corrected" on /usr partition. I believed it did it.
Well, to make a long story short, if I ftp some .tgz on a temporary
directory, then I give the command

gzip --test -v *.tgz

many times, I got different "file corrupted", sometimes on the first
file, others on the n'th file, others all files seems good!!!! If the
gzip doesn't give me an error message, the file is decrunched rightly.

I give some other times fsck, and only one time it tell me that there
were errors.

Since I applied the last pciide patch, I even tried to boot with a
generic 1.3.2 kernel, with the same results.

Some of You have a good suggestion ?? I feelin' so baaaaad......

Bye bye,
Marco.