Hi there! I've got a unique scenario and google didn't offer much assistance, so I suppose I can ask here.
I intend on selling my current system to a friend and rebuilding a system with a better GPU/CPU with the money. However, I would like to keep my hard drive and operating system (he'll get his own hard drive). If I purchase the same kind of motherboard (AsRock Pro3), would I in theory be able to simply plug my hard drive in and boot up windows 8 with all of my programs or am I missing something? Thanks.
The CPU will be going from a 3570k to most likely a 3770k and the GPU will be a 560ti to a 7870.
If this isn't possible, could I just reformat my hard drive and reinstall the OS without any problems?
It will also depend on the hard drive controller, before and after, being set for AHCI.
BUT, why are you selling your system and then replacing it with an almost identical system? It sounds like all you need to upgrade is the Graphics card, and help your friend gather and build his system.
Here is what I did with different setups, I installed win 8 in the same computer on 2 separate drives in the same system, I unplugged one drive, setup windows 8, then unplugged that drive and plugged the other in and setup windows 8 on the second drive. The second drive I did not have to activate in the same system. after setup was complete I put the drive in a spare computer. Windows 8 found all the drivers for that board. I had to activate that OS by choosing activate by phone after activating the system was stable. I now had two OS built from one system. I had to buy a new CD key for the first computer that I used to setup windows 8, or reactivate it using the original key. One way or the other I still had to buy a new key for one of the computers, but setups went good, no system crashes in the second computer.
Even if you change motherboards you should be fine as long as you only have that OS loaded on one PC. I've done it several times with OEM versions of windows, you will have to do the phone activation and they will ask if it's being installed on only one system, but you should be fine.