In the AMD FX giveaway rules the 8 cored FX CPU is listed at having a value of $300 USD. While there is no indication which model it may be, regardless it appears it is priced very competitively.
screenshot of the statement
It is currently expected that the AMD FX CPUs will be released around September 19th.
FWIW the giveaway is only open to US and Canadian residents.
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