Welcome to the MacNN Forums.

Eug Wanker · Feb 4, 2006, 10:47 AM

It seems some people are getting video glitches with the iMac Core Duo 20" with 256 MB video RAM. The glitches are inconsistent but show up more often in apps like Front Row:

Video

I suspect this isn't a "Version A" iMac thing, and more a driver issue that will get corrected with OS update, but I'm just guessing.

hldan · Feb 4, 2006, 12:01 PM

Originally Posted by Eug Wanker

It seems some people are getting video glitches with the iMac Core Duo 20" with 256 MB video RAM. The glitches are inconsistent but show up more often in apps like Front Row:

Video

I suspect this isn't a "Version A" iMac thing, and more a driver issue that will get corrected with OS update, but I'm just guessing.

Just attribute this video issue to Front Row being new. Remember it took Microsoft 3 years to get Media Center to be acceptable. It's a great addition to XP now but it was buggy for a long time. Front Row most likely takes up a lot of system resource and will get better with newer releases. Not making excuses but you have to keep in mind that you are playing a movie inside of another program which is why DVD player plays the movies perfectly outside of Front Row. I still think that Front Row is very well done for being out such a short time but of course no glitch is acceptable when people are spending their money.
Apple rushed out Front Row to compete with Microsoft since this seems to be the year for the home media experience.
Most likely a newer version will appear at Macworld 2007.

eddiecatflap · Feb 4, 2006, 12:24 PM

funny how it's always at the lower part of the screen and affects the 256 models

could the extra vram be faulty ?

DoctorGonzo · Feb 4, 2006, 12:31 PM

Apple declared my new 20" Core Duo with 256MB of VRAM D.O.A because of this problem.

But it is a big problem and I'm worried that my replacement machine will have the same issue.

Eug Wanker · Feb 4, 2006, 12:32 PM

Originally Posted by hldan

Just attribute this video issue to Front Row being new. Remember it took Microsoft 3 years to get Media Center to be acceptable. It's a great addition to XP now but it was buggy for a long time. Front Row most likely takes up a lot of system resource and will get better with newer releases. Not making excuses but you have to keep in mind that you are playing a movie inside of another program which is why DVD player plays the movies perfectly outside of Front Row. I still think that Front Row is very well done for being out such a short time but of course no glitch is acceptable when people are spending their money.
Apple rushed out Front Row to compete with Microsoft since this seems to be the year for the home media experience.
Most likely a newer version will appear at Macworld 2007.

Except that the glitch is not just with Front Row. Conversely, it doesn't occur with other Macs running Front Row either.

eddiecatflap · Feb 4, 2006, 12:34 PM

oh gawd , i hope mine doesn't have this problem

mduell · Feb 4, 2006, 01:17 PM

Originally Posted by hldan

Just attribute this video issue to Front Row being new. Remember it took Microsoft 3 years to get Media Center to be acceptable. It's a great addition to XP now but it was buggy for a long time. Front Row most likely takes up a lot of system resource and will get better with newer releases.

Front row uses a lot of resources, wtf? It's a basic media player with a 10 foot interface. Nothing special or resource intensive.

As far as this being a "Rev A" issue, it certainly affects Rev A, but don't let that scare you away. Rev A is has a record of being no better or worse than the later revs, and bugs frequently persists across multiple revisions.

macintologist · Feb 4, 2006, 02:10 PM

Phew, thank god I ordered the 17" with 128VRAM

icruise · Feb 4, 2006, 02:49 PM

Originally Posted by macintologist

Phew, thank god I ordered the 17" with 128VRAM

That's what I was just thinking. But I'm pretty sure that this will be correctable via a software update of some kind.

mduell · Feb 4, 2006, 03:26 PM

On the same idea as iCruise, has anyone with the problem tried underclocking their VRAM?

baw · Feb 4, 2006, 03:50 PM

I've never encountered that problem on my Intel iMac with 256MB VRAM.

codex57 · Feb 4, 2006, 07:09 PM

How weird. That video was really helpful. I had no idea what "tearing" meant.

However, it doesn't happen on my computer. I have a 20" Dual Core 256VRam 250Gig HD with 1Gig Ram factory installed. That seems to be the most common config that people are reporting having problems. I can't get it to do that tearing at all. Mine works perfectly. I ordered and received mine right in the middle of all those people reporting their problems.

I guess it's a random thing. Certainly doesn't affect all Rev A 20" iMac's with 256VRam

acorder · Feb 4, 2006, 11:30 PM

Mine is scheduled to arrive next week. I will see if it has the same issue. I also ordered mine with only 512mb of RAM from the factory. I will use it for a couple of days that way before I put in the 1GB so-dimm I bought and see if that changes anything...

Macadvo · Feb 5, 2006, 12:33 AM

Count me as one of the lucky ones that doesn't have this problem, but my sympathies do go out to those of you affected by this

pauken · Feb 5, 2006, 08:30 AM

see this: a different thread...

http://discussions.apple.com/thread....1&tstart=0

eddiecatflap · Feb 6, 2006, 01:05 AM

looks like a dodgy os-x build then , not hardware related at all

thank gawd fer that , i'm sure a software patch will sort it out !

macintologist · Feb 6, 2006, 02:28 AM

Yep, it's software-related.

rotuts · Feb 7, 2006, 11:09 AM

a complement to MacNN for a very fine thread here. as usual the Eug started things off in fine fashion and Id like to thank Pauken for the ref to the apple discussion.

a frined of mine new to mac is going to get the iMac with the max RAM and im going to set it up. at least if he gets the later build there will be an update as some point. Apple probably in their interests does not want this to crimp sales.

is it only video apps that this effefts?

cheers rotuts

rotuts · Feb 7, 2006, 11:22 AM

Why does apple do this? they seem to have pulled the thread at their site that points to the build problem and the vram.

don't they know thisis HelpFull? do they read any of this?

too bad so sad. they are more and more like M$ arn't they

boo booo

acuthbertson · 02:03 PM

I just recieved my 20" with 256mb video as well, and am experiencing this issue. Everything else seems to be great, it's just FrontRow that looks angry. i sincerely hope this is just an patch issue and not anything I'll have to ship my iMac back for.

BTW, I'm running OSX build 8G1171 which according to the thread at the Apple forums is the troublesome one.

DoctorGonzo · Feb 8, 2006, 03:42 PM

Apple took my machine back, and my replacement isn't due to ship until March 6th.

rotuts · Feb 8, 2006, 04:46 PM

well the thead reappeard, so my appologies to apple

however, if they continue to 'take machines back' are they simply installing an earlier build or is something else going on or more likely:

is Apple On The Whole ignorant of the whole problem which bodes poorly for a timely solution??

DoctorGonzo · Feb 8, 2006, 05:49 PM

Originally Posted by rotuts

however, if they continue to 'take machines back' are they simply installing an earlier build or is something else going on or more likely:

is Apple On The Whole ignorant of the whole problem which bodes poorly for a timely solution??

I think they are just trying to "bring back machines from the wild" so-to-speak for further, in-depth hardware analysis to ensure they really know what's behind the problem.

rotuts · Feb 8, 2006, 06:12 PM

well I hope so. however, wouldn't they just try the two builds on the gazillions of machines they have in the pipe line?

anyway a very interesting problem to follow, yes?

cheers

rotuts · Feb 8, 2006, 08:34 PM

well I hope so. however, wouldn't they just try the two builds on the gazillions of machines they have in the pipe line?

anyway a very interesting problem to follow, yes?

cheers

acuthbertson · Feb 8, 2006, 08:55 PM

I'm just going to wait and see if there's an issue once a update comes out, since it's under warranty for a year and video issues in frontrow isn't going to kill me at the moment.

eddiecatflap · Feb 8, 2006, 10:59 PM

i agree , front row is ok , but not a deal breaker imo

i've got it fitted via a hack to 3 macs and never use it

Gamoe · Feb 9, 2006, 01:05 AM

Originally Posted by rotuts

Why does apple do this? they seem to have pulled the thread at their site that points to the build problem and the vram.

don't they know thisis HelpFull? do they read any of this?

too bad so sad. they are more and more like M$ arn't they

boo booo

Even though you say it re-appeared, why should it have disappeared at all? And why are other threads locked? Honestly, this type of senseless censorship is what keeps me from being an active member of the Apple Boards. The MacNN forums (san INtelliTXT) are much better for such discussion.

I have a friend who I think is switching to the Mac. He was looking into the iMacs, but I'm not sure now whether to recommend a Dual Core, or one of the G5 iMacs left now.

eddiecatflap · Feb 9, 2006, 02:27 AM

i heard it affects the last batch of G5 imac's too

it's obv. the ati card / driver at fault

x600 in the G5 and X1600 in the DC

Simon · Feb 9, 2006, 04:17 AM

Originally Posted by Gabriel Morales

I have a friend who I think is switching to the Mac. He was looking into the iMacs, but I'm not sure now whether to recommend a Dual Core, or one of the G5 iMacs left now.

He can go on and get the Intel iMac. It's clearly a driver issue. Chances are he'll get a model with a newer build and not have the issue. If not, either Apple will fix it via SU in the next few days or your friend can just get hold of another Install DVD (the one with build 8G1171) and the issue will be over. This is really not a show stopper.