[rmcpherson]

That's true, although the latest stock ubuntu HVM AMIs (14+, I believe) have the SR-IOV driver already and use it by default. Older AMIs need to have it installed and enabled on the AMI. I believe enhanced networking is only available on HVM amis.

[oavdeev]

This problem definitely existed with official 14.04 (HVM) AMI, though I haven't re-tested this recently, they may have fixed it. It did have some kind of SR-IOV driver but it was too old.