you have the short explain here:
About E5 if you have O/S Linux, use command shell
or dmidecode -t4
It's wrote if you have .
I don't have this model under my hand for answer more precise
(Sandy Bridge several model exist.... your first question is about SSE4)
Unfortunaly for AVX it's could be more complex you have (AVX,AVX-I,AVX-2)
Better you read here
Chapter compiler reference
--code generation options
Example in topic related flag CORE-AVX-I
You read between the lines
(processors in process technology smaller than 32nm)
So appropriated only to IVY ....
To be sure ,I have verified small machine
Even the entry of series model G6xx Sandy have SSE 4.1 SSE 4.2