

Developer's dream come true: New MacBook Airs now support two external displays - gaborcselle
http://9to5mac.com/2012/06/20/retina-macbook-pros-run-three-external-displays-refreshed-airs-get-dual-external-display-support/

======
gaborcselle
This is a pretty big deal for designers and developers who love dual-display
setups, e.g. for looking at code and docs at the same time. Until now you had
to lug around a 15" MacBook Pro to get dual external monitor support.

~~~
Ralith
Or use something other than a MacBook. That's an option too.

~~~
gaborcselle
The vast majority of developers I know use some version of the MacBook.
(However, that could be the San Francisco / New York tech bubble that I live
in.)

~~~
flatline3
I don't understand the allure of the laptop for developers.

For me, performance easily beats portability. I _also_ have a laptop, but I'd
never use it as a primary desktop.

~~~
13rules
I run my own company and have a home office and a regular office, each with a
mouse, keyboard, and big monitor. With my laptop I can just take it back and
forth - all files come with me and the machine is in the exact state when I
boot it up at home as when it was at the office.

If I need to go out of town, I just take the laptop with me and I can do
everything I would normally do, just with a smaller screen.

At least for web development, speed usually isn't an issue ... putting in an
SSD drive a year or so ago, though, was the best thing I did - very noticeable
speed increase!

So, for me it's a convenience factor.

------
RossDM
So where are the affordable Thunderbolt displays? Will they even exist for
this generation of tech?

~~~
duaneb
I would imagine that there are converters to DVI/HDMI.... I hope?

~~~
bingbing
Monoprice has this:

[http://www.monoprice.com/products/product.asp?c_id=101&c...](http://www.monoprice.com/products/product.asp?c_id=101&cp_id=10114&cs_id=1011409&p_id=8118&seq=1&format=2)

It doesn't support chaining more thunderbolt devices, though.

~~~
veemjeem
All this does is split the video into 2 identical signals. Note their fine
print: "the two outputs of this monitor will always be the same"

------
cmelbye
Wow, that looks amazing. Forgive my ignorance (I don't use external displays
with my MBP), but how is this done? Does each display connect to the next
display with Thunderbolt daisy chaining?

~~~
modarts
Exactly, the thunderbolt displays have outputs that you can daisy chain with.

------
bwh2
I've been running two external displays for some time on my MBP. One mini
display port, one USB. The USB has a mostly negligible lag.

~~~
HalibetLector
I've been doing the same and the lag isn't the issue. The real problem is high
CPU usage. I can only use the usb monitor for looking at text, anything more
(like opening a webpage or watching a video in youtube) and the computer slows
to a crawl (I'm using the first unibody macbook pro, pre-thunderbolt).

------
mikeevans
Do the displays have to be Thunderbolt displays? Seems really expensive.

~~~
jpxxx
Negatory. The Thunderbolt port is really just passing through a DisplayPort
signal - any DisplayPort monitor will do.

Displayport degrades nicely into HDMI, DVI, or VGA with an adapter, so sky's
pretty much the limit.

The new MacBook Pro does also have a HDMI port which can do all the same.

~~~
gaborcselle
I didn't know that.

Since I have Cinema Display with DisplayPort, could I do MacBook Air >
Thunderbolt > Cinema Display?

~~~
jpxxx
No sir. For (presumably) dumb (presumably) Apple Reasons, a non-Thunderbolt
display cannot be involved in that chain at all.

I'm not sure why. This is not gospel, by the way - I don't know if this was a
limitation of the prior MBAir or else the signalling scheme in play.
1-800-APL-CARE can clarify.

~~~
veemjeem
As I mentioned in another post, non-thunderbolt displays cannot interpret
packet data. When you use a dvi to thunderbolt adapter, it's simply
translating the pins, not decoding packets. Your laptop's thunderbolt chip
would realize you're connecting a normal display and send the usual display
signals rather than packet data.

If you put this normal display at the end of a thunderbolt daisy chain, it
would be the responsibility of the last device on the chain to convert the
video packets into signals, something I doubt intel would put into their
specs, requiring all devices that implement lightpeak to also decode video.

I think adapters are sometimes bad in this regard, people will think if the
adapter fits, it should work the way they think it should. Back in the day
when parallel ports and scsi used the same 25pin connectors, lots of people
destroyed devices thinking they could hook their hard drives to their parallel
port.

------
TomatoTomato
Can the macbook pro retina handle 4 thunderbolt displays (2 on each port as
with the Air) + HDMI?

~~~
jpxxx
Negatory. The total volume of pixels the Mac can push is the limiter. As you
add monitors, the Mac will eventually black out the laptop display and spend
the pixels externally. Beyond that it'll simply refuse to light up the display
it can't feed. Doesn't matter which port they're headed out of.

Three sizeable displays appears to be the limit.

Note: A Thunderbolt display _can_ pass along enough signal for another
Thunderbolt display. But not two extra on the chain. And for (presumably) dumb
(presumably) Apple Reasons, a non-Thunderbolt display cannot be involved in
that chain at all.

tl;dr: give Apple all your money

~~~
veemjeem
probably not apple reasons since thunderbolt is really just intel's lightpeak
spec. you probably can't chain a non-thunderbolt display at the end of the
chain because the data packets are probably encoded with some device id, and
if it doesn't match the current hardware, it would just forward it along the
chain, so when these packets arrive at the non-lightpeak compliant display, it
wouldn't be able to interpret it.

tl;dr: normal displays don't read packet data

~~~
teilo
This is a limitation of Apple's Thunderbolt display, not Thunderbolt itself.

Thunderbolt is designed to allow displayport at the end of a chain. For some
reason, Apple chose not to support connecting a displayport adapter directly
to a Thunderbolt display, but you can put a daisy-chained device in-between
your Thunderbolt display and your displayport display, and it will work.

------
Ralith
Rather presumptuous to imply that developers in general care about MacBook
design tweaks, isn't it?

~~~
rch
The hyperbole didn't sit well with me either.

------
drivebyacct2
That's why I pulled the trigger and bought mine yesterday.

