I have a Sapphire HD 7950 Vapor-X OC with Boost 3GB GDDR5 and MSI R9 380 GAMING 2G, 2GB Crossfire can be managed with these graphics cards? if so, how
No it's not compatible. You can CrossFire your 7950 with the following;
I would recommend using another 7950, or selling your current 7950 and upgrading to a R9 380X or an R9 390.
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