Strange problem, MacBook Pro will not load OS X

[louishen]

I am trying to fix someones computer (MacBook Pro 2007 4,1)

It boots to the Apple screen but then hangs, this happens to the hard disk (10.6) and DVDs and a usb stick (installing 10.7)

Done all the usual stuff (safe mode, reset NVRAM and SMC) but no luck. Will boot into single user mode but that's it.

Oddly enough it will boot into an Ubuntu DVD and even happily run Ubuntu, I was thinking it could be the graphics card

Will try and install Leopard, but anybody got any ideas

Note, the first thing I did was put it into target disk mode, so the data is safely backed up

 

[pigoo3]

It boots to the Apple screen but then hangs, this happens to the hard disk (10.6) and DVDs and a usb stick (installing 10.7)

My first thought was that the HD was dead/dying...but if you say that it also will not boot from an OS DVD or a bootable USB stick...then this is a bit of a situation (assuming that these are sources that this computer can boot from)...not the incorrect gray disks or anything like that.

And since you tried the other good stuff (PRAM reset, SMC reset, safe mode)...not too much else to try.

Just for the heck of it...maybe try removing & reseating the ram. Maybe there's some sort of weird ram issue.

- Nick

p.s. Given that it will boot from the Ubuntu DVD...this would verify that the optical drive works...and seem to verify that the logic board is ok.

 

[louishen]

Thanks pigoo3

I amazingly had 2x1 gig sticks that were an exact match so put them in, still no luck.

But after installing Ubuntu, which wiped the whole drive clean I also remembered I had a Snow Leopard retail disk sitting on the bookshelf

After the RAM swap and the Ubuntu install, the Snow Leopard disk booted just fine, and now after a few restarts it is happily running software update

Why the Lion installs were not working is a mystery, since it meets the specs, but it shows how sometimes Ubuntu can at least get a machine booted up and show that the motherboard is not the problem

It had Snow Leopard installed to begin with, so now its restored to its previous state

 

[pigoo3]

It had Snow Leopard installed to begin with, so now its restored to its previous state

Well that's great news! If that Snow Leopard disk didn't work...this problem was going to be a real "Head-Scratcher"!

Regarding the Lion (10.7) install attempts (via DVD and USB). I know that you know that Lion was download only (except for the USB drive Apple did sell)...is there a chance that the bootable Lion DVD & USB stick that were created...could have been made improperly (an error in the process)?

I don't know if you made them or someone else. Of course if the bootable Lion DVD and bootable Lion USB stick have worked in other computers...then I guess we still have a mystery.

Again...congrats & good news that Snow Leopard installed ok!

- Nick

 

[louishen]

UPDATE - the thing overheated again and the problem returned. I have now fixed it, and the main problem was overheating

Symtoms: Loading any OS including booting the OS halts halfway through. The macbook is running very hot, especially 3 points on the underside are extremely hot (where the processor and 2 graphics chips are, near the back of the case).

Turns out is was not a software problem as such, just that the logic board was getting too hot, even during boot-up from cold.

It was the thermal paste drawing heat from the processors to the heat sink at the back of the case. The installed thermal paste had almost completely worn away over time so there was very little thermal contact between the processors and the heat sink.

Took the logic board out, cleaned out the case of any minimal dust and carefully cleaned away the old paste from the copper contacts on the heat sink and the tops of the chips, with alcohol

Applied new thermal paste (ifixit has a guide on how to do this properly) and put the whole thing back together. Now runs cool and happily runs and installed OSX Lion.

So lesson is, if she's not booting anything except single user mode, and you can feel distinct hot spots on the underside, it may be time to get some thermal paste and re-unite the processors to the heatsink

Thought this mac was a dead duck, but now its running for hours without toasting my legs

 

[chscag]

Nice work, bringing a Lazarus computer back from the dead! (Don't let that go to your head now)