OEMS would require a new os to as the hardware is only compatible with the factory os. Also, drivers aren't standard,and would need to be backuped prior to the installation of a new os. As for the ocmpatibility, just make sure the powersupply motherboard cable (24-pin ,etc...) is the same on the motherboard. I would highly not suggest upgrading the motherboard.
Roger
I was thinking about upgrading my mother board for my computer. I was wondering if there are any steps I need to take and how to do them to find out compatibility of mycase and motherboard. Like I have a Compaq Presario SR1330NX Desktop:
http://h10025.www1.hp.com/ewfrf/wc/document?lc=en&cc=ca&docname=c00280664&product=443740&dlc=en&lang=en
And was wondering how I would go about finding a motherboard that would upgrade my system and allow me in the future to perform other upgrades and such? But yeah, are there any real steps needed, and if so, could you explain and help me?

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