I am currently running Zwift on a Sony S series laptop i7, with 12 gig of Ram but only a lowly GT640MLE mobile graphics card.
It works and it works well enough for Zwift to be enjoyable.
However I realise I might be on the limit of minimum performance.
So I have been looking at the Alienware Alpha, to sit next to my xbox one under the TV in the cave. Would the base level i3 4GB alpha be a good choice for Zwift?
There was a post yesterday on the “Zwift on NVidia GTX 960”
Eric C. from zwift posted the following information on the Dell Alienware Alpha. It sounds like you are good to go :<)
"Any integrated graphics will never quite be up-to-snuff to get ultra or high settings. You can find a list of our minimum, recommended, and extreme settings on our website here: http://zwift.com/what-is-it#specs
But you’ll need a pretty beefy system to get up there. We’ve had a lot of luck with Dell’s Alienware Alpha which is a tiny desktop system that produces some great results for around $550. Of course you need to provide the keyboard, mouse, and monitor (or television).
The system I have at home is a Desktop system similar to Jon’s: a 4GHz i7-4790k with 16gb of RAM and an Nvidia GTX 970 Superclocked. That’s already pretty ridiculous 
Eric C. 17 hours ago"
We’ve tested them in-house and it’s pretty great. Zwift requires far more graphics power than CPU power.
An i3 with a powerhouse graphics card will go much further than an i7 with a mediocre one.
thanks Eric,
BTW, I just realised that if I plug my laptop into my xbox one hdmi in I get a really neat setup where I can snap media (music, video, youtube etc) along side Zwift and control that media with voice/gestures through kinect. Makes for a pretty neat such up. heck I can even make a skype call without taking my hands of the bars!
Sorry to dig up an old thread, but any chance you could share what FPS one would get on the Alienware Alpha and what setting it would run at?
So I have a Core i3 alpha which I have upgraded to 8 Gig or Ram and an SSD.
Although early on I did get occasional frame rate issues I have to say its now running great at 1080p settings, so much so that I have not seen any frame rate issues recently nor do I feel the need to measure the FPS.
Very happy with the Alpha and Zwift