It seems you missed the second sentence of my post.
"However the OP may have to install the original operating system at
own time and expense before warranty work can commence."
At that point everything is covered since the computer is back to
original configuration.
Depending on the specific hardware issue, it may be necessary to
install the original operating system before warranty work can
proceed.
Warranty work includes anything from first contact with the
manufacturer about the issue which is often phone support.
As an example I had a problem with my Toshiba laptop hard drive about
a year ago.
It originally shipped with Windows XP but Windows Vista was currently
installed.
There was no need to reinstall Windows XP since the hard drive
diagnostics are not dependant on the operating system.
For some hardware issues I may have needed to install Windows XP to
verify it was not a driver etc.
But they certainly would not troubleshoot a Windows Vista issue and no
one should expect them to.
The warranty is not void but I may need to return to original
configuration before warranty work.
--
Jupiter Jones [MVP]
http://www3.telus.net/dandemar
http://www.dts-l.org