There was a lot of political conflict at AMD when Raja was there, The RTG Group was formed to apease Raja who wanted to split Graphics off AMD completely, of course with him at the top of this new independant graphics company, the RTG Group was a compramise.
That didn't calm the politicking. Raja was not 'offisially' sacked, no excutive ever is, i do think he was told to go by Lisa, the moment he was out she moved her own team in and BAM! She doubled his Vega Intergrated Graphics performance while at the same time cutting power in half, just like that....
Intel are now stuck with him, i say that because i don't believe he's much good.