Dual Monitors using ONLY the Thunderbolt Port


macrumors newbie
Original poster
Aug 2, 2012
Hi, I have a decently new MBP (Bought August 2011) and I am about to buy two Dell monitors. I know I can use the thunderbolt for one monitor, and a usb->hdmi converter for the other, but my question is, is there an alternative? Can i use two displays with only the Thunderbolt port by using a splitter such as the one linked below?

I guess my question is, will a splitter mirror my screen on both monitors or allow me to mirror on one monitor and extend on the other?

Thanks for all your help!



macrumors 68040
Jun 16, 2007
no, unless you have the rMBP.

You can only do 1 from the TB and then USB to DVI (which will lag)


macrumors 6502a
Feb 9, 2008
Monoprice doesn't explicitly say how the two HDMIs work, but I would have to imagine that it's just going to mirror the same output on both.

From what I've been able to gather, even though you can chain Thunderbolt-aware monitors off of each other to get multiple monitors off of one Thunderbolt port, I have not seen anyone yet manufacture an adapter that plugs into Thunderbolt and gives you two DisplayPort connections for two discrete external monitors. It seems like an obvious device for someone to make, but so far it does not exist...

I did run into this: http://www.sapphiretech.com/presentation/product/?cid=4&gid=1010&sgid=112&pid=1413&psn&leg=0 -- it looks like it might do the trick for you, with the caveat that it will allow you to hook up two monitors, but to the computer it will appear as just one monitor instead of two separate ones. The monitor that the computer sees, however, will be either double the width (3840x1080) or double the height (1920x2160), and this appears to be configurable via DIP switches on the adapter. The adapter will then spread the image out over two monitors.

So it seems like there is no perfect solution out yet, unless you're willing to consider ditching your current monitors and replacing them with two Apple Thunderbolt displays.

-- Nathan

Joseph Farrugia

macrumors regular
Jul 31, 2011
Malta (EU)
According to the customer reviews on monoprice, that splitter only mirrors, it does not extend.

Lot more expensive, but does what you are asking

that Matrox is limited to:

"a stretched desktop of 3840x1200 (2x1920x1200) across two displays"


"Runs(s) in clone mode and shows the same content on all displays"

Quotes pasted directly from their product page.

I would suggest doing a search on that model, there have been a number of incompatibility reports especially due to refresh rates & Matrox have not exactly been forthcoming……