DDR3 in LPDDR3 slot ?

[NYJimbo]

Customer brought in a MacBook air (Why, because he knows I don't work on them ? ) and If you start it normally, it will get the apple logo and the spinning wheel and sit there forever.....

If you start it in the recovery mode and run disk checks it comes out fine. No power or booting issues.
However if you start it in Diagnostic mode and tell it to run ram tests it will shutdown in about 1-2 minutes,
full power off. Customer thought it was an overheat but its not hot and I did a fan clean anyway (was clogged).

So it appears that if I do anything outside of the ram diags (D key on boot) it will not shut down but it will also not fully boot. Customer left it running for hours (spinning wheel) and I left it for 45 minutes just to be sure it wasn't some lengthy file repair/update/cleanup that needed to complete.

Right now I am suspecting a bad ram chip but it appears MacBook Air's use a LPDDR chip and I don't have any in stock. Can I use a similar performance DDR3 chip or will the voltage diff cause some damage. Searching google I see yes and no responses. I want to be sure to not only NOT damage the machine but also not create some instability during diags because of the voltage diff.

Thanks for any help or guidance.

 

[Markverhyden]

If I remember correctly RAM is soldered onto the logic board.

 

[NYJimbo]

If I remember correctly RAM is soldered onto the logic board.

Yeah, I guess I have to open it back up to check. But if that's it then they may be screwed.

 

[Markverhyden]

Yeah, I guess I have to open it back up to check, but if that's it then they may be screwed.

Apple has been less than helpful from a R&M perspective. Started with the iMacs when they were using adhesives all over the place instead of mechanical fasteners. Then they started with the soldered on RAM in the Air. But that has expanded. Now it's that way with the MacMini. And then some if not all laptops. When I bought my Retina a while ago I had to get the max RAM at the time as it was soldered on. Really ticks me off.

 

[NYJimbo]

Seems they put the ram chips on a small ($200+) logic board. When I first opened it I didn't notice the shape and thought it was a ram stick.

I am heartbroken...

 

[Markverhyden]

You know what Gomer said - Surprise, Surprise, Surprise!!!! LOL!!!

 

[NYJimbo]

You know what Gomer said - Surprise, Surprise, Surprise!!!! LOL!!!

This is the kind of thing that makes me shake my head in disgust.

Soldering ram to logic/motherboards.
Eliminating easy access doors to ram, fans, hard drives, etc on laptops.
Removing HD I/O or other critical lights on laptops and desktops.
Eliminating dialogue from bootup/shutdown procedures in Windows.
Removing BIOS startup info and options.

These and other things are so important for computer users and techs. I think the only reason they do this is because they want your computer to die as soon as possible so you will buy a new one.

 

[FremontPC]

That's great. At least $500 just for the part.

Makes me wonder what the Hackintosh scene is like these days.

 

[altrenda]

What do you mean "If you start it in the recovery mode and run disk checks it comes out fine. No power or booting issues." It boots into the recovery partition OK, but not the OS? It appears to be the Mac equivalent of a borked MBR. This is where something like Disk Warrior or TechTools could fix it, but since you don't work much on Macs, it probably isn't worth it to you to buy them. OnyX might work for you.

When I have a Mac that won't boot, I try booting from an external drive to eliminate the hard drive or a corrupted OS. If you don't have a Mac disk, try a Linux disk in an external DVD.

Macbook Airs have heating problems that sometimes can be fixed by an SMC reset ( http://maccrazy.com/macbook-air-heat-fan-noise )

Macs aren't that different hardware wise from other computers, but the software is different. Trying to fix them without tools isn't any different from trying to fix a Windows machine without them.

 

[NYJimbo]

What do you mean "If you start it in the recovery mode and run disk checks it comes out fine. No power or booting issues." It boots into the recovery partition OK, but not the OS? It appears to be the Mac equivalent of a borked MBR.

What I am saying is if you run pure built in ram diags it shuts down. Maybe the wording was confusing. It will boot but not all the way and will not shut down. I think its spinning due to some ram error that may be treating it like a disk error. Windows sometimes will produce spurious errors at boot that will bitch about the hd when it really is the ram. The fact that only ram testing makes it shutoff looks like a ram issue to me.

 

[altrenda]

Got it.

just for fun, if you haven't already, try the smc reset.

With the power off and the charger attached, press the (left side) Shift-Control-Option keys and the power button at the same time. After the chime, let them go.

Might not make a difference, but worth a try.

 

[NYJimbo]

Got it.

just for fun, if you haven't already, try the smc reset.

With the power off and the charger attached, press the (left side) Shift-Control-Option keys and the power button at the same time. After the chime, let them go.

Might not make a difference, but worth a try.

Oh yeah, I learned all the resets a while back. Had a few Macbooks come in not booting and with some googling , managed to find all the different reset and restart tricks.

 

[FremontPC]

Hopefully this guy has a Time Machine backup or the like, otherwise if the SSD is soldered too, you would have to try a backup via Disk Utility in Recovery Mode or Target Disk mode with another Mac.

I've had pretty good luck booting Macs with Ubuntu 12.04 Live CD, does anybody know if there's a lightweight linux distro that works with Macs?

 

[gadgetfixup]

To answer your question about LP DDR3 memory if you insert DDR3 it just won't use it. I've never seen it damage anything but rather, either just beeps or no video. We started stocking the LP stuff for ASUS laptops as many of those use the LP memory chips lately.