Unfortunately, this could easily be real, but I am not too worried. Everything that you have said has been used by viruses, and this is just an amalgamation of many different viruses.
Windows 7 is not a bad OS. Yes, it is targeted, because it is Windows, and made by Microsoft, but Apple Macs and Linux do get many viruses, and just as bad. My best advice to you is to follow good security guidelines, and then you will be absolutely fine on Windows.
This virus sounds like it targets the hardware, and will not have a lot of sophisticated cloaking and removal protection, which is good. It sounds to me like a good real-time, updated AV will very easily block this malware, before you even realise it, and before it has time to infect you.
The method viruses use to re-infect after a format is to infect the MBR. However, this can be fixed using specialist tools under supervision, so this does not worry me.
One thing if it does get on to your system. All of your clocks would have to be turned back down by the AV, and so a good AV would turn them back down and save your hardware, a bad AV will remove the malicious code, but will not fix the clocks, and your hardware would be dead. This would split the good and bad AVs.
Therefore, it won't be long before a malware removal expert or a company like Symantec will release a specialist tool for removal, to remove it, and fix the clocks properly for all.
A hard disk is damaged by wiping Sector 0. This is instant, and irreparable. However, overclocking until meltdown is not instant (though is irreparable). I now see a problem. If you immediately break the hard disk, then you won't be able to overclock until meltdown. If you overclock, then it meltsdown, then you will not have time to finish off the hard disk. So, to co-ordinate these is very difficult, bordering on impossible.
Therefore, I think this will slip in and out of fashion, if it even exists at all. Follow good security guidelines, and you will be protected from this.
Just my thoughts!