please recommend a disk-exercising program?

[Michael David Crawford]

Check the downloads section at the disk manufacturer's website.  All the 
disk vendors have utilities that can test their disks.

Generally these utilities can use proprietary commands to exercise 
self-test functions that generally aren't accessible to non-proprietary 
test code.

Most of the utilities are DOS boot disk images.  You make either a 
floppy or a CD from them, then boot off of it.

Mike
-- 
Michael David Crawford
mdc at prgmr.com

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