1.) OEM copies are forever locked to the motherboard, so they cannot be 'moved' to another computer and the motherboard cannot be replaced.
2.) You can perform a clean installation only, not an upgrade.
3.) You receive no technical support from Microsoft beyond that standard updates, knowledge base, etc.
It's not riskier, but you need to be committed to the computer you're buying/building and capable of handling most problems yourself, with the help of others like in these forums. That's the trade-off in price.
John
What are the pros and cons of installing them in an not new computer?
Will OEM be riskier in case of reactivation or change of components?
TIA

Chowhound
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