Q: Mouse cursor lags with external monitor

Great! Sami951, I've an Air so can't test dual thunderbolt/mDP output.

When u connect the mDP to DP cable. Did u connect it to a monitor or only plug the cable in it?

I mean is the port actually outputting signal to a monitor? Or even plug in the cable cause the mouse skipping?

if the problem occurs with just the cable plugged in. then maybe it can solve by using another cable perhaps?

I think we've narrow down the problem a lot since the beginning. Anyone know where to file a bug report to apple to make this issue official?

Hi,

mDP to DP cable connected to laptop and screen (screen turned on, using it via DVI): lag

mDP to DP cable connected only to laptot: no lag

I was thinking this might have to do with the Thunderbolt 2/Displayport 1.2 socket and the way it is handled in OS X, since my previous Macbook Air (mid 2012) has Thunderbolt 1 (Displayport 1.1) socket and it is working fine. Then again, reading this thread it looks like also Thunderbolt 1 equipped devices are having the same symptoms so maybe it is not directly caused by the later port ...

I'll need to try a dual link DVI adapter to get 2560x1440 resolution. At the moment I'm guessing it will work fine, but would of course rather have it work with the mDP <-> DP cable ...

Cheers, Sami

Hi!

I have quite close symptoms and set-up: the mouse doesn't skip, but is sluggish after hooking up an external monitor using mini-displayport. Using HDMI and single-link DVI did not seem to cause this issue (an dual-link DVI adapter in Norway is over 160$...).

My set-up:

* MBP 17" mid-2010 running Mavericks 10.9.1.

- 2,53GHz i5

- 8GB RAM

- Intel HD-graphics (internal)

- NVIDIA GT 330M 512MB

* Philips 272P4 LED monitor 2560x1440.

* Mini-DP -> DP cable.

So with all the mentioned set-ups, it seems like the constants are MacBook and the DisplayPort-input on an 2560x1440 non-Apple monitor.

Espen.

Oh... And if  anyone have noticed any processes using more RAM or CPU after hooking up the new display, it could be helpful to leave a note on this to...

I have exactly the same problem as described above with......

• Mac Mini 2012 Late
• Processor  2,3 GHz Intel Core i7
• Memory  4 GB 1600 MHz DDR3
• Graphics  Intel HD Graphics 4000 1024 MB
• Software  OS X 10.9 (13A603)

connected to a brand new

• Dell U2713H display
• with a Mini DisplayPort to DisplayPort cable
• and resolution 2560x1440

I have mouse Lags! anyone solved the problem?

Same problem here with Retina MBP13 HD 5000 connected via Dell cable miniDP to DP and u2713H.

Had to apply fix from http://embdev.net/topic/284710 to fix unsharpening. (maybe this fix introduces bug?)

each time after mac goes to sleep mouse pointer starts to lag.

If I go to monitors menu and enable DP 1.2 lag vanishes until next sleep...

with lag or without it I see mouse pointer trail on monitor.. it is not present on Mac screen...

do you also have white trail on pointer?

No, no white trail for me. All the rest is the same. Can you upload a screenshot with the trail to see what you mean?

I have tried to capture video with iphone but camera cannot capture it... white trail of mouse pointer is mostly visible on light gray (top of e.g. safari window)... there is no visible trail on builtin display on macbook...

I have connected MBP 15 2012 with discrete GPU... it doesn't have mouse lag problem... but it also have mouse trail on my u2713H...

same Dell cable... miniDP to DP was used

Here is more on "mouse trail" http://en.community.dell.com/support-forums/peripherals/f/3529/t/19513238.aspx

It is called RTC overdrive and it looks like there is no option in Dell menu to disable this "feature"...

anyway, this is not related to problem that mouse start to lag just after waking up MBP with HD5000 from  sleep ...I could live with RTC but wakeup problem with mac is a real problem (I do not want to go to menu to disable/enable DP 1.2 each time my macbook wakes...)

I have the same problem. New (Haswell) MBP w/ Mavericks. My old Air doesn't have the problem. Turning off the monitor for 10s then back on again seems to fix it about half the time. Very frustrating. Given that this has been reported as far back as 2009, I do not think we should expect Apple to fix this problem. They simply do not care. Shame.

I bought a dual link DVI adapter to try how it works with 2560x1440 resolution, end result: works fine, and there is no mouse lag. So for me this "fixed" the problem, of course would be much nicer to just be able to use the displayport cable. I also hate having to pay 99 euros for a simple adapter.

Exact same issue here. Late 2013 13" Retina MBP, external monitor is Dell U3014 connected with a Mini DisplayPort to DisplayPort cable.

Mouse lags until I enter the monitor menu. I have a couple DP-DualDVI adapters lying around here, will give that a shot.

I rearranged my work desk, and opened the MBP's lid instead of having it in clamshell. ...it is now all just fine. Not logical though...

I have the same issue. Mouse lags and gets useless when I plug in a external display.

Computer:

MaBook Pro Retina 15-inch, Late 2013

16 GB

OS X 10.9.1

External display:

Hp LP2465

Connection:

HDMI port to DVI port with adapter

I have been having these exact issues with my Dell U2713H connected via DisplayPort to a 2013 MacBook Air 13". It even makes the keyboard unreliable as it seemingly misses both key up and down events when it's spacing out every 1 or 2 seconds, making keys not work and even more annoyingly, stick.

I've tried sleeping/waking the computer, disconnecting/reconnecting the screen, turning the screen on/off and numerous other things. Nothing seems to help reliably.

Today I went through the menus on the screen and on a lark enabled DisplayPort 1.2 (Menu, Display Settings, DisplayPort 1.2) and it's been fine for a couple of hours now. I don't dare disconnect should it start misbehaving again, but at the very least it's a thing to try if you're having problems as well.