Extreme slow screenbehaviour with 2nd screen

willybNL

macrumors 6502
Original poster
After connecting a second screen (via VGA as external screen) my macbook is always real slow.

Things like expose, frontrow but even just moving a window take seconds instead of msec's.
If i disable 1 of the screens (thus or the macbook screen or the external) all is fast again.

Is there something i can diagnose in os x, can't imagen this should be considerd normal.

FYI: both screens running 1280, 1 x800 (macbook) 1 x1024 (@60hz; My Sun LCD screen).
Also tryed other screens (my Samsung HDTV), but gives same result, real slow window things...
 

MGLXP

macrumors regular
Sep 29, 2005
245
7
I noticed the exact same thing on my Macbook Pro 2.0Ghz w/X1600 256MB and 2GB RAM. I also noticed this with a Mac Pro 2.66GHz in the store that was connected to two screens. Everything (especially dashboard and expose) becomes quite jerky. I think it may have to do with OS X since I think both these systems should be able to drive two monitors quite nicely.
 

willybNL

macrumors 6502
Original poster
MGLXP said:
I noticed the exact same thing on my Macbook Pro 2.0Ghz w/X1600 256MB and 2GB RAM. I also noticed this with a Mac Pro 2.66GHz in the store that was connected to two screens. Everything (especially dashboard and expose) becomes quite jerky. I think it may have to do with OS X since I think both these systems should be able to drive two monitors quite nicely.
Yep... that's it... I got 1GB ram on my Macbook 2.0Ghz.... so it really should be no problem at all, but it still is.

Are there more people having this problem? Could it be some program interfering? (I closed all programs, even rebooted etc.etc.etc.).

I also noticed in iMovie HD that some of the effects show very very strange behavior... maybe faulty videocard?
 

willybNL

macrumors 6502
Original poster
Today it became worse:

it's always when i notice my macbook is hot, my macbook is real slow.
Not just slow... real slow. Unworkable. (i first noticed the screen, but it's becomming so worse sometimes the whole system is renderd useless for some time)

When this is happening: Even rebooting or powerdown does not help. The chime on boot will take 10 seconds to come, os x will go 100% all the time....

but only intil the fan jumps on... all becomes faster and faster... till: nothing slow anymore to be found. (note; looks like the fan does not always jumps on thus. a).

First i thought it was software, now i'm almost convinced (due to the very long boottime before the chime) it's hardware.

I've got the firmware updated, but it looks like it become worse since then. (I notice it more and more, due to iTunes and iDVD hicking when this is happening when i'm away from the mac.).

Does anybody else notice the same thing?

note; Nothing installed like Core Duo Temp, thus can't read that out.
Did notice that most of the times i also get something like this:
Sep 24 20:24:42 Computer-van-William kernel[0]: IOAudioStream[0x3671a00]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last clip position (53e,3263)->(542,be9).
Sep 24 20:24:42 Computer-van-William kernel[0]: IOAudioStream[0x3671a00]::clipIfNecessary() - adjusting clipped position to (541,3263)

And after that today i also got
Sep 24 20:26:53 Computer-van-William kernel[0]: PRB0_TAIL: 00000898
Sep 24 20:26:53 Computer-van-William kernel[0]: PRB0_HEAD: dce008ac
Sep 24 20:26:53 Computer-van-William kernel[0]: PRB0_STRT: 02120000
Sep 24 20:26:53 Computer-van-William kernel[0]: PRB0_LEN: 00000003
Sep 24 20:26:53 Computer-van-William kernel[0]: SRB0_TAIL: 00000000
Sep 24 20:26:53 Computer-van-William kernel[0]: SRB0_HEAD: 00000000
Sep 24 20:26:53 Computer-van-William kernel[0]: SRB0_STRT: 02121000
Sep 24 20:26:53 Computer-van-William kernel[0]: SRB0_LEN: 00000003
Sep 24 20:26:53 Computer-van-William kernel[0]: PGTBL_CTL: 3ffc0001


no idea what is is...
in my event log just around the time that it's real slow.
 

kainjow

Moderator emeritus
Jun 15, 2000
7,958
3
I kind of noticed this too when I bought a 23" ACD and used it with the MacBook's display. Now I just use the ACD display only.

I bet it's because of the integraded graphics?