I keep reading about malware that survives formating of a hard drive.
Does it write to bios ?
I use Linux and have not seen this.
google for "root-kit"
formatting may not get rid of it
but i think deleting a partition and starting from scratch should do the job
https://threatpost.com/new-bios-implant-vulnerability-discovery-tool-to-debut-at-cansecwest/111710
and
https://threatpost.com/inside-nls_933w-dll-the-equation-apt-persistence-module/111128
interesting reads - related to the topic it would seem.
Not to mention NSA spyware included in some manufacturers hard disk chips.
http://www.technobuffalo.com/2015/02/17/nsa-spyware-hiding-hard-drives-made-by-wd-seagate-and-others-report-says/
The only way to get rid of that is not to use their disk. But then you risk the same malware but from the Chinese.
Don't be afraid to run a flash upgrade on your BIOS either, many of the better motherboards have a jumper option to reset the BIOS from scratch and then you can add any upgrades you need.