Ok some background info first.
My secondary pc's ssd recently died. That ssd was actually an upgraded part (i.e. it was a hdd in the original config when this pc was purchased) , so when I did the upgrade I had to do a telephone activation for the win7 oem that came originally with this pc. Subsequently this win7 installation was upgraded to win8 during the discount period when win8 launch.
So to the part I wish to get advice on:
Now that I have the ssd replaced, do I need to install win7 first and then the win8 upgrade? or is there a way to install the win8 upgrade directly?
I'm just a bit concerned that since I already had one harddisk change for my win7 activation, I'm not sure if microsoft will allow it this time. Would be glad to hear from those who had similar experience. Thanks.
Your oem license is not tied to your hard drive. It's tied to the computer itself — more specifically the motherboard.
Simply replace the hard drive and start reinstalling windows like you would. It should also activate without any issues, even after post-upgrading. If after upgrading Windows doesn't activate, simply call Microsoft and tell them you're reinstalling Windows after repairing your computer, they will walk you thru the process.
The official word from Microsoft is that Windows 8 Upgrade media can only be installed on a drive that contains a prior version of Windows. and not on a bare drive.
Technically, you can simply insert the Win 8 Upgrade media and install it normally but you later hit a snag when you try to activate it afterwards.
There is an unofficial way of fixing that error and you can perform it without breaking any EULAS or TOS's since you legitimately own a copy of Windows 7 and it's license key.
If this method fails on you, you can follow it up with the old 'double install' trick, which involves installing Win 8 twice.