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andygoldberg · Oct 3, 2009, 02:44 AM

My macbook pro just suddenly started showing 4 desktops on the screen, tiled, one in each corner. If I run a reset on the pvram, Control+Option+P+R, The screen will come back as a single full screen, until it gets to the blue screen, it will then become tiled again, and then the desktop is also tiled. Also if you hook up an external display it shows only one desktop, not tiled. It doesn't seem like hardware since the pvram reset and the external both show a single image, but how do I troubleshoot software on a mac? I am a windows convert, so please help out.

Thanks!

ibook_steve · Oct 3, 2009, 03:22 AM

Stupid question: are you just activating Spaces? Try pressing the default key for it, F8, if you are in Spaces to get out (or just click on one of the desktops). If not, can you describe a little better what you mean by "tiled?" It sounds to me like you have Spaces in your list of startup items.

Steve

andygoldberg · Oct 3, 2009, 06:25 PM

I looked under utilities and Spaces was not enabled. I enabled it and I got 16 windows 4 in each corner. I just selected the single desktop so I can get back to 1 in each corner. I put a screen shot here: http://andy.queencreekgoldbergs.com/tiled-display.jpg

Andy

AKcrab · Oct 3, 2009, 07:08 PM

That is very bizarre.

ibook_steve · Oct 3, 2009, 08:33 PM

Very, very weird. Have you tried changing the resolution? Has the panel in this machine been replaced? If so, it could be incompatible. Have you tried resetting PRAM (cmd-option-p-r at boot until second boot chime; maybe you weren't holding it long enough)?

Steve

reader50 · Oct 3, 2009, 08:38 PM

If you create a new user account and log into it, is the tiling present in the new account too?
System Preferences -> Accounts -> [+] button below the accounts list.

• If tiling is not present in a new user account, it is a preferences problem in your main account. Get back to us, we'll guide you through what to delete.
• If the tiling is present in a new user account too, then boot from the install DVD. See if the tiling comes up there.

andygoldberg · Oct 3, 2009, 09:05 PM

Thanks for the suggestions. I have triedresetting the PRAM. Once I reset the PRAM, it boots with a single screen like a normal mac, but when it gets to a blue screen, right before the desktop apears, it goes to a tiled display again. I have tried changing the resolution. Unfortunately I don't have the OS discs to be able to reload the OS without going out and buying a copy. It seems to me a software issue.

I tried creating a new account and the same problem exists. It seemsto be happening right before the desktop loads. But once it happens, it will stay like that even during boot, unless I reset the PRAM and then like I said before, it goes back to tiled right before the desktop appears.

AKcrab · Oct 3, 2009, 09:12 PM

Try a safe boot: Mac OS X: Starting up in Safe Mode

andygoldberg · Oct 3, 2009, 09:31 PM

OK, I reset the PRAM and then booted into safe mode, it gets to the blue screen and then, it goes tiled again, even in safe boot.

andygoldberg · Oct 3, 2009, 09:36 PM

I also tried exchanging out the RAM, but no go.

reader50 · Oct 3, 2009, 09:45 PM

You need to obtain (or borrow) OSX Install discs. The problem is either hardware (expensive) or corruption in the operating system. You need to boot from an install disc and see if the problem goes away. If so, use the install disc to do an Archive & Install - this replaces all the system files, but preserves your user folder, applications, etc.

If those solutions fail to work, then you know it has to go in for repair.

turtle777 · Oct 3, 2009, 10:23 PM

When you do a screenshot (Cmd + Sh + 3), what do you get ?
One screen or all four ?

-t

andygoldberg · Oct 4, 2009, 08:20 PM

The screenshot is of a single desktop.

P · Oct 5, 2009, 03:25 AM

Hm. Can you try changing the resolution to 1024*768@60Hz. and see what happens?

One of the things resetting the PRAM does is return the Mac to a default resolution and update frequency. Once the system boots, it reads the correct current res from a file on the disk and changes it again.

andygoldberg · Oct 5, 2009, 10:21 AM

Okay, I reset the PRAM and used a program called SwitchResX to change the resolution to 1024x768@60Hz. Still no go. Is there a better way to change the refresh rate than using third party software?

olePigeon · Oct 5, 2009, 12:29 PM

Try booting from your OS install DVD and see if that solves your problem. If it does, then try uninstalling SwitchResX. I have a feeling that may be your culprit.

andygoldberg · Oct 5, 2009, 12:53 PM

I tried booting from the install DVD after resetting the PRAM again. I get a single grey screen with the apple logo and spinner until it get to the language selection and it goes to four screens again.

P · Oct 5, 2009, 01:05 PM

I meant changing the resolution from inside System Preferences, but I doubt the result would have been any different.

So, what do we know: with the low default resolution after a PRAM reset, it works. With the higher normal resolution, we get into some weird twilight zone. I would suggest playing with the resolutions and number of colors a bit just to see what happens, but it's looking like you're going to have to bring it in.

olePigeon · Oct 5, 2009, 01:11 PM

Take it into an Apple Store if there is one near you. Have one of their techs look at it, they might be able to figure it out. I've never seen anything like this.

andygoldberg · Oct 5, 2009, 03:56 PM

Originally Posted by P

I meant changing the resolution from inside System Preferences, but I doubt the result would have been any different.

So, what do we know: with the low default resolution after a PRAM reset, it works. With the higher normal resolution, we get into some weird twilight zone. I would suggest playing with the resolutions and number of colors a bit just to see what happens, but it's looking like you're going to have to bring it in.

I didn't see a place to select refresh rate just resolutions. I triaed all the resolutions available, but it didn't change it from being four screens.

I also did bring it to the Genius bar at the local Apple store and they were stumped also, they had never seen it. They sggested a flat fee service of $300.00, but that is a little out of budget for me. I don't mind doing the work myself, just want to narrow down the parts before buying stuff I don't need.

turtle777 · Oct 5, 2009, 04:37 PM

Originally Posted by andygoldberg

I also did bring it to the Genius bar at the local Apple store and they were stumped also, they had never seen it. They sggested a flat fee service of $300.00, but that is a little out of budget for me. I don't mind doing the work myself, just want to narrow down the parts before buying stuff I don't need.

It's a hardware defect. You probably need to be an EE or Apple tech to "narrow" that issue down.

-t

P · Oct 5, 2009, 05:25 PM

Do you have access to Techtool Deluxe? It's included with Applecare, and it has a hardware test loop that might be useful. I do think that you will need help from Apple with fixing it, though.

turtle777 · Oct 5, 2009, 05:40 PM

Originally Posted by P

Do you have access to Techtool Deluxe? It's included with Applecare, and it has a hardware test loop that might be useful. I do think that you will need help from Apple with fixing it, though.

I think this thread nicely documents that this is a very rare problem. None of the 'NN members have every seen or heard about this, and even the Apple Genius was surprised.

What are the odds that TechTool will find something that will lead to a "software" fix ?

-t

P · Oct 6, 2009, 04:44 AM

Small, but I figure it's worth a shot if Apple wants $300 to fix it.

andygoldberg · Oct 6, 2009, 12:14 PM

Unfortunately I don't have Applecare CD to get the Techtools. Does anyone know where I can get it?

P · Oct 7, 2009, 07:13 AM

Here, but you need to have paid for AppleCare to be able to download it.