No, this is not a fake processor.
It seems like the item is similar to a 9700KF but only has half of its cores active. Contact the seller for clarification.
He remains silent when asked.
Review the BIOS configurations as well. There might be an option to limit the CPU to a specific number of active cores.
Avoid purchasing if the seller refuses to engage in conversations.
Avoid suspecting a fake scenario. Consider restarting BIOS settings and verify Windows doesn't restrict available cores via msconfig.
Thank you
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