w_tom wrote:
> Any hardware that can be damaged by software is defective

Unfortunately we accept such defects in commodity hardware to get
the lowest price.

> Any processor that would overheat (a slow temperature increase) due to
> excessive 'software' commands is throttled or turned off by existing
> hardware.

I believe this is implemented in software (BIOS) on at least lower-cost
x86 motherboards. A magic CPU mode is used to achieve independence from
the OS, its accessible memory, and CPU registers like the MMU. However,
it's too much to expect that there is no bug in the CPU, motherboard,
or BIOS, from any vendor, that could be exploited to block the fan
feedback. All the more so since there are sound reasons for the vendor
to provide loopholes so bootable software can test or tweak the BIOS
functions. And, of course, the BIOS itself is vulnerable, since it
is typically stored in flash memory for convenience of fixing bugs.

> And yet some 'computer experts' also insist that a disk drive can be
> destroyed by software.

SCSI disks, at least, have many stored modes that can be set such that
the disk can't be used until software aware of the proper modes (ie not
the driver) puts them right. I believe I also managed to lose the
built-in bad track map once, clearly a defect in the drive but to be
expected with the amount of software embedded in the drive (which BTW
is also vulnerable to rewriting in many drives).

Prices being what they are, a not-so-new disk or motherboard damaged
by the hypothetical virus in such a way that it can be repaired by the
right software tool or chip replacement is probably not worth what it
would cost to hire the appropriate expert to do it.