2011 iMac - MDP(via Thunderbolt) to DVI converter causes mouse to skip/jump

[MACza]

Hi!

OK - I had my 2011 21.5" iMac now for a week. Loving it so far!!

BUT there is an issue - I am using my 23" Samsung monitor from my retired PC (Good riddance!!! ) as a secondary display via a MDP to DVI connector (the official white Apple one).

The funny thing is, when the MDP is plugged into the Tbolt port - it causes my mouse pointer to skip/jump. It is extremely bothersome, especially when trying to do precise graphical/photo work. I have tried all settings, other mice etc. The skipping/jumping happens when the 2ndary display is switched off.

The skipping/jumping DOES stop as soon as I remove the MDP to DVI connecter from the Tbolt port though - talk about strange!!! .

I must still test this when the 2ndary display is OFF - I seem to recall that it was fine when the 2nd display was switched on as well. I will test this more later today to have some properly tested results.

Anyway - has anybody else experienced this mouse pointer skipping/jumping happening when using the MDN to DVI converter???

Any pointers or advice will be much appreciated

 

[MACza]

Well, I just confirmed my suspicions!

Case 1:
Second display switched off, but MDP to DVI connector connected to 2nd display.
Result 1:
Mouse skips/jumps every 4 seconds (testing just by moving the mouse cursor in a circle continuously)

Case 2:
Second display switched on and connected via MDP to DVI connector to iMac.
Result 2:
Mouse is silky smooth, absolutely NO skipping or jumping of the mouse cursor!

Case 3:
MDP to DVI connector unplugged from iMac.
Result 3:
Mouse is silky smooth, absolutely NO skipping or jumping of the mouse cursor!

THUS - the MDP to DVI connector causes the jumping/skipping of the mouse cursor when the MDP to DVI connector is connected, but the 2ndary display is not switched on.

Fortunately this is not as bad as I originally feared - I will mostly work with both displays powered up. It is just that sometimes I would only use the iMac by itself and will then have to unplug the MDP.

I hope Apple can fix this - where does one formally log an issue with Apple on technical issues?

Thanks!

 

[gcthompson]

That is strange, I have 2 external DVI monitors plugged in and don't experience the same issues. How much VRAM does your video card have?

 

[sth]

Report it to Apple, probably an issue with the Thunderbolt drivers. http://bugreporter.apple.com/
I'd also post the question in the official support forums since Apple seems to read those as well.

 

[MACza]

Thanks sth - I will do that. It seems this is a problem that has been reported before, will post some links a bit later...

Here is a link - seems this was previously fixed via a patch, must have slipped back in with Snow Leopard/Thunderbolt introduction:

https://discussions.apple.com/message/8917257#8917257

 

[Bardofar]

Well, I just confirmed my suspicions!

Case 1:
Second display switched off, but MDP to DVI connector connected to 2nd display.
Result 1:
Mouse skips/jumps every 4 seconds (testing just by moving the mouse cursor in a circle continuously)

Case 2:
Second display switched on and connected via MDP to DVI connector to iMac.
Result 2:
Mouse is silky smooth, absolutely NO skipping or jumping of the mouse cursor!

Case 3:
Result 3:
Mouse is silky smooth, absolutely NO skipping or jumping of the mouse cursor!

THUS - the MDP to DVI connector causes the jumping/skipping of the mouse cursor when the MDP to DVI connector is connected, but the 2ndary display is not switched on.

Fortunately this is not as bad as I originally feared - I will mostly work with both displays powered up. It is just that sometimes I would only use the iMac by itself and will then have to unplug the MDP.

I hope Apple can fix this - where does one formally log an issue with Apple on technical issues?

Thanks!

Im also gonna connect a second monitor to my 27" imac, mdp to dvi. Im gonna go to the store tomorrow and get a original Apple connector. Ill let you know if im experincing the same issue with the skipping mouse.

 

[danseq]

I'm having exactly this problem with a new MacPro 3.33Ghz machine.

I have three monitors.

1. 2560x1600 30" samsung 305t on a Gefen extender
2. a 17" Dell on a USB->DVI displaylink adaptor

Mouse has been fine up till now with those.

When I added a 40" Sony 1080p TV (using a 3rd party minidisplay to HDMI adaptor) that's when I started having the mouse skipping problems. It's driving me nuts. When I remove this display and reboot, the problem goes away.

@Bardofar--did the apple branded MDP to DVI work to solve the problem?

More:

https://discussions.apple.com/thread/3099117?tstart=0