midrange graphics: amd or nvidia?

I am looking for a notebook with something like 6650/6770 or gt540m and i can't decide which is better at games and power consumption, nvidia or amd? That's the first question.
Nvidia optimus is a nice feature, but i see a lot of complaints all over the internet that discrete gpu doesn't always switch on when it's needed. Especially in the old games like HL2 and others.
I heard that amd has similar to nvidia's optimus feature. How it is called? Does it have same problems with games or i can turn amd gpu on and off manually?

 

AMD automatic switching is called BACON (greasy name aint it?)

the 6770m is going to pwn the gt 540m to dust, the gt 555m is a competitor although a little bit slower

AMD also uses manual switching either via a physical switch (vaio S series) or via desktop right clicking (all the other AMD switching equipped hardware)

I dont like automatic switching since its buggy, and yes this applies to AMD as well

 

long story short: yes.

you want either amd or nvidia graphics. any of the options you mentioned are fine. avoid intel. don't listen to anyone who says otherwise.

 

but nvidia doesn't provide an option for manual gpu swithing, doesn't it? Otherwise i don't understand why there are so many people complaining on official nvidia forum that they can not force nvidia gpu to work in some games.
upd:
there is even a thread on WoW forums about nvidia optimus http://us.battle.net/wow/en/forum/topic/2593006174

 

no nvidia dont offer manual switch

 

But you kinda have do it in a dumb way by setting it to default on the High Performance for Nvidia's Optimus.

The newer HP dv6/dv7 61xx Series using something similar with BACON with their 6770/6490 but they don't have a manual switch anymore. They don't even have the dumb way of doing like for Nvidia either.